• Browser built in viewer
• PDF Viewer
• Universal Document Viewer
• Google Docs View
• Google Drive View
• Download Document [pdf]
Not Your Device? Search For Manuals / Datasheets:



File Info : application/pdf, 130 Pages, 72.44MB

Document Document

·oR ENGINEER S AND EN GINEERING MANAGERS

MARCH 29, 1976

Th e first 16-k bit MOS RAM achieves the highest ca pa city for random-access memories, with no sacrifice in speed. The IC
has an access time of 250 ns,

or about that of current 4-k bit units. And the new memory uses the 16-pin package of some 4-k versions, simplifying expansion of present systems. See p. 101.

J30URNS®
New, Low-Cost Cermet Trimming Potentiometer outperforms the other "small- change" models!

Bourns super cermet performance delivers again. Our new Model 3352 trimming potentiometer handles more power ... takes more shock and vibration ... has a lower CRV ... and is easier to set than, for example, the "Model 91". Naturally, Bourns super cermet performance is comparably priced. You can depend on it.
The 3352 is a %" diameter, single-tum device with
an easy (but stable) three-way thumbwheel adjust. It can be wave-soldered, and withstands board wash-
ing processes with minimal (1%) TR shift. The 3352
is available TODAY in a variety of pin styles to suit your requirements.
Compare performance . . . specify Bourns Model 3352. For complete details, contact your local Bourns representative ... or the factory direct.

COMPARE PERFORMANCE

Power

.75 watts at 40°C .5 watts at 40°C

Electrical Angle 230°
---<
Adjustability ± 0.053

180° ± 0.05 3

Torque

5 oz.-in. max.

6 oz.-in.

Shock

lOOG'smax. ± 23 VRS

50G's no VRS spec.

Vibration

30G'smax. ±23 VRS

lOG's no VRS spec.

Contact Resistance Var.

13

23

Rotational Life 200 cycles

200 cycles

Temp. Range -55°C to +125°C I -55°C to +125°C

Nobody knows more about trimming potentiometers than we do

TRIMPOT PRODUCTS DIVISION· 1200 COLUMBIA AVE., RIVERSIDE, CALIF. 92507
CIRCLE NUMBER 284

Hot-molded resistors provide low temperature coefficient and unmatched reliability.
The Resistance Temperature Coefficient of Allen-Bradley hot-molded fixed resistors is typically less than 200 PPM over the entire resistor range shown in the normal equip-
ment operating temperature of + 15°C to + 75° C. Excellent RTC ratings have al-
ways been an Allen-Bradley benefit. And consistency of Allen-Bradley resistors means repeatable results and tight performance patterns. Allen-Bradley resistors offer the lowest cost-on the board-where it counts!
+~1~17).G

,

!Oi

13·

KT

10s

10

~
is unsurpassed. Over 700 million unit test hours without a single failure.

/h-~
Insulation and resistance element integrally molded into one solid structure.

~~
characteri stics offer out-
standing protection against
surges and transients.

Quality in the best tradition.

f.!~ ~~!;:;~H~tJ;~;~RADLEY

Milwaukee, Wisconsin 53204

EC1 13

CIRCLE NUMBER 2

-

CIRCLE NUMBER 4

How to Design Your

Power Supply for $66

You get the complete scltemoti< diagram, and ports list with operating and installation instructions when you spend $66 for an Abbott Model "RN" power supply. Two years in development, this model represents the latest state of the art in power module design. It features close regulation ( 0.1%), low ripple ( 0.02%), automatic short circuit and complimentary overvoltage protection and continuous operation in a 160°F ambient.
Abbott Engineers followed specific design criteria in engineering these modules. First, the electrical design was carefully engineered to insure that all components operate well within their limits, under "worst case" operating conditions. Second, the thermal design, including case construction, was carefully made to insure that the maximum temperature limits of all components are never exceeded. Then the size and weight of these modules were controlled to a minimum, without sacrificing reliability. Finally these units were thoroughly tested to make certain that all design and performance specifications were met.
So, you can build your own power supply using our schematic diagram if you want to-but we think we can build it more

reliably and for less cost, simply because we have been doing it for ten years. Put our power supply in your system first and try it. Examine its performance. We think you will be pleasantly surprised at the quality, adherence to specifications, and the reliability you find in the Abbott Model "RN".
Any output voltage from 5 to 100 volts DC with current from 0.15 to 20 amperes is available. Many of the popular voltages ore carried in stock for immediate delivery. Please call us for attractive O.E.M. discount prices.
Abbott also manufactures 3,000 other models of power supplies with output voltages from 5.0 to 740 volts DC and with output currents from 2 milliamperes to 20 amperes. They are all listed with prices in the new Abbott catalog with various inputs:
60 ~to DC 400~to DC
28 voe to oc 28 voe to 400~ 12-38 voe to 60 C\;t

Please see pages 1037-1056Volume1 of your 1975-76 EEM (ELECTRONIC ENGINEERS MASTER Coto log) or pages 612-620 Volume 2 of your 1975-76 GOLD BOOK for complete information on Abbott Modules.

Send for our new 60 page FREE catalog.

abbott transistor

LABORATORIES,

NCORPORATED

general offices

eastern offl~e

5200 W. Jefferson Blvd. / Los Angeles 90016

1224 Anderson Ave./Fort Lee, N.J. 07024

(2~ 3) 936-8185

Telex: 69-1398

(201) 224-6900

Telex: 13-5332

"SEE US AT ELECTRO '76 l.E.E.E. SHOW IN BOSTON, BOOTH NO. 2112"

CIRCLE NUMBER 5
6

Sr. Vice President, Publisher
Peter Coley
Editors
Editorial Offices 50 Essex St. Rochelle Park, NJ 07662 (201) 843-0550 TWX: 710-990-5071 Cable: Haydenpubs Rochellepark
Editor-in-Chief George Rostky
Managing Editors: Ralph Dobriner Michael Elphick
Associate Editors: Dave Bursky Samuel Derman Morris Grossman John F. Mason Stanley Runyon Michael Shunfenthal Edward A. Torrero
Contributing Editors: Peter N. Budzilovich, John Kessler Alberto Socolovsky, Nathan Sussman
Editorial Field Offices
East Jim McDermott, Eastern Editor P.O. Box 272 Easthampton, MA 01027 (413) 527-3632
West David N. Kaye, Senior Western Editor 8939 S. Sepulveda Blvd., Suite 510 Los Angeles , CA 90045 (213) 641-6544 TWX: 1-910-328-7240
Jim Gold , Western Editor 1454 Burrell Court San Jose, CA 95126 (408) 246-6094
Editorial Production
Marjorie A. Duffy, Production Editor Tom Collins, Copy Editor
Art
Art Director, William Kelly Richard Luce, Anthony J. Fischetto
Production
Manager, Dollie S. Viebig Helen De Polo, Anne Molfetas
Circulation
Manager, Barbara Freundlich Trish Edelmann, Gene M. Corrado
Information Retrieval
Peggy Long
Advertising Promotion
Paul K. Hogue
Promotion, Creative Layouts
Manager, Albert B. Stempel Maxine Correal, Nancy Gordon
ELECTRONIC D ESIGN 7. March 29, 1976

Across the, Desk

Bit-error rate analysis needed
The article "Squeeze More Data into Mag Tape," by Messrs, Bentley and Varsos (ED No. 21, Oct. 11, 1975, p. 76 ) should have included a more substantial analysis of the high bit-error rate associated with Miller encoding in a bandwidth-limited (tape recording) appEcation , Such an exhaustive analysis is included in a paper by W. N. Waggener of EMR-Schlumberger titled "Optimum Detection of Delay Modulation ."
The introduction of the paper states, "The performance of delay modulation (DM) has been widely misunderstood. The small lowfrequency content and a sharply peaked spectrum at about 0.4 bit rate has led potential users to conclude that DM is an efficient coding technique.
Such a conclusion is unwarranted and, in fact, the performance of DM is 3.5 dB poorer than NRZ using an optimum detection bandwidth of twice that of NRZ, If the bandwidth of DM is limited to the spe'Ctra.l region less than the bit rate, a considerable penalty in bit error performance is paid. This seems to contradict the article by Messrs. Bentley and Varsos.
W. D. L ewis Computer Syst ems Sp ecialist General Dynamics Data Systems Services
Authors reply
The analytical paper referred to by Mr. Lewis has been reviewed with interest and appears to be highly pertinent to the subj ect ma-

terial. We greatly appreciate his letter, especially in directing our attention to this analytical study,
Our article, though, in no way contradicts or confirms the result of Mr. Waggener's study. For recording applications, where output signal-to-noise ratios greater than 20 dB are experienced in practice, bit-error rates (BERs) better than 10-6 are attainable even under the most pessimistic performance curve of Waggener's analysis, This is in agreement with the clajms of BER performance, as stated in our artide.
The 10-s BER performance has been previously reported in reference 2 of our article, and in other new references that have been published more recently. These are listed here for your information:
1. Breikss, Ivars P., "High-Density Data Recording," IEEE Sp ectrum, May, 1975, pp. 58-62,
2. Jensen, T. A., and Starkey, M., "80 MBPS Recording," Di gital Design, September, 1974, pp. 28-35 .
S. G. Varso s Enginee1· Principal Lockheed Electronics Co. 16811 El Camino Real Houston, TX 77058
Beating the standard set for HP-25
The programmable pocket calculator truly provides the scientist and engineer of today with a personal computer. The presently available calcu lators are comparable in computing power to the early fu ll-scale computers. It will be interesting to watch for parallelisms in development.
The absolute machine language
(conti nued on page 8)

Electronic Design welcomes the opinions of its readers on the issues raised in the magazine's editorial columns. Address letters to Managing Editor, Elec-
tronic Design, 50 Essex St. Rochelle Park, N.J. 07662. Try to keep letters under 200 words. Letters must be signed. Names will be withheld on request.

EL ECTRONIC DESIGN 7. March 29. 1976

OPTRON
OPTICALLY COUPLED
ISOLATORS
NEW HIGH ISOLATION VOLTAGE " DIP" SERIES OFFERS HIGH TRANSFER RATIO
Now, OPTRON provides a 5 kV isolation voltage capability for its standard six pin plastic dual-in-line isolators. A new, unique internal design allows high voltage isolation while still maintaining a high current transfer ratio. The 5 kV DC or 3750 rms AC feature is available for all devices in OPTRON's popular OPI 2100 and OPI 3100 series.
OPTRON's extended " DIP" series includes JEDEC types 4N25 through 4N38A, features complete interchangeability with popular industry types and provides an inexpensive coupler for every application. Devices are available with isolation voltages of 1500, 2500 or 5000 volts with minimum current transfer ratios rang-
ing from 2.0 to 500%. OPTRON's " DIP" and
a full line of other isolator packages with isolation voltages to 50 kV provide the versatility required for maximum electrical and mechanical design flexibility.
1.5 kV isolation with
. .60% current transfer ratio.
Phototransistor base lead OPI 102 available. Hermetic T0-5
package.
OPI 110
1OkV isolation and 40% current transfer ratio. 4 µ,Sec switching time in low cost miniature plastic package.
Detailed technical information on " DIP" and other isolators as well as all OPTRON optoelectronic products .. . chips, discrete components, assemblies, and PC board arrays . . . is available from your nearest OPTRON sales representative or the factory direct.
@. OPTRON, INC. 1201 Tappan Circle Carrollton, Texas 75006, u SA 214/242-6571 · TELEX-73-0701 TWX-91 0-860-5958
CIRCLE NUMBER 6
7

ACROSS THE DESK
rcontinued from page 7)
programming in the early computer days emphasized minimization of the number of machine cycles and storage locations us.ed. As execution and s.torage got faster and cheaper, especially relative to the labor component of programming, economic considerations changed the factol'S to be minimized. As a result, higher level languages became popular.
Modern programmable pocket calculators have limited speed, limited program and data storage, and are programmed in machine language. We are back to counting and minimizing the number of locations used and instructions executed. Since these programs are often entered from the keyboard by . highly trained personnel, the number of keystrokes needed to enter the program should also be minimized.
The HP-25 is a popular calculator of this class, and since a book of application prog11ams comes with it, there is a standard :to try to beat. Here is a program that calculates the factorial and that is uised the same way as the one in the book, but consists of fewer instruction entered in fewer keystrokes-and runs faster. Both versions use one data storage register.
STO 0
1
STO x 0
1
fx# y
GTO 03 RCL 0 GTO 00 .Can some other reader beat this?
H enry E. Schaffer Professor of Genetics Norith Carolina State University Box 5487 Raleigh, NC 27607
D for diode is recommended
Reference Mr. Thomas' letter "An 'Excellent' Guide to Miniature Relays" (ED No. 22, Oct. 25, 1975, p. 7), perhaps I might express the hope that the use of the designa-

tion CR be abandoned for diodes. Not only does it suffer from the
disadvantage of obscurity in this context (D is admirably clear and not used, so far as I am aware, for any other circuit element) but CR is needed for "contactor," for which it is regularly used by electrical engineers to distinguish contactors from low-power supervisorand-control relays (RL).
Please therefore continue to use the common sense D for diode and perhaps we may hope that one day the American National Standards Institute terminology will be amended to conform to what is a natural and therefore preferable usage.
W. Lyons Jt. Managing Director Claude Lyons Ltd. Ware Rd., Hoddesdon Herts, ENll 9DX United Kingdom
Misplaced Caption Dept.
Sorry. That's Bartolome Esteban Murillo's "Street Arabs," which hangs in the Alte Pinakothek in Munich.
Need for kits with .an understandable program
I want to commend ELECTRONIC DESIGN for bringing out two fine articles relating to microprocessors. In the January 5, 1976 issue (ED No. 1), on page 46 there is the ED special report on microprocessors,

and the even more interesting article on page 96, "Incorporate a Calculator Chip," relating to use of a calculator chip in a number-processing data system.
It is ce:dain that both of these articles will go far to advance the microprocessor concept, not only for controlling systems, but for mathematical calculations involved in doing so.
For example, a calculator-microprocessor combination could be designed to orient a flat-plate mirror, one of many to be used for concentrating solar heat onto ·a boiler to generate megawatts of electrical energy. Solar energy thus should go a long way toward solving the energy crisis now facing humanity.
The Altair system, as pointed out in the microprocessor article, is operable using Basic. Many of us engineers know how to use Basic but have difficulties understanding assembly languages as offered in the simple microprocessor kits. Hence, there is an urgent need for putting these kits together wi.th understandable programs for ease in arranging I/ 0 interfaces.
For that reason, the article on the calculator chip was particularly appealing. For instance, calculator kits are av·ailable from a number of sources. One could assemble such a "pocket calculator," modify it in the direction of process controlling, and at the same time learn some very good fundamentals of microprocessor use.
Robert H. W eitbrecht Vice President, R esearch & De-
velopment Applied Communications Corp. P.O. Box 555 Belmont, CA 94002
A matter of fact
Thank you for your enlightening editorial in the January 5, 1976 issue of ELECTRONIC DESIGN. Irrespective of whether a different consultant would have altered the course of history, I would like to know if the progency of the Czar and the Czarina should in fact have been identified as Czardines.
Robert E. Bilby Maooger Marketing Services Weston Instruments 614 Frelinghuysen Ave. Newark, NJ 07114

8

ELECTRONIC DESIGN 7, March 29, 1976

_ _ meA1uRemen1
'bf!.' COffiPUTATIOn
innovations from Hewlett-Pockord

MARCH 1976

MEA.SUREMENrJll;OMPUTA.TION: NEWS

HP's 9825A powerful new
desktop computing system
Because of special features and high speed , the 9825A can compute, handle peripherals, and control instruments, all effectively at the same time.
Combining calculator and minicomputer features, HP's new 9825A offers you a "personal" computer oriented toward the solution of problems in the fields of engineering, research and statistics.
The 9825A has a combination of features never before found on a desk-
top calculator. With the live keyboard,
the user can examine and change program variables, perform complex calculations, call subroutines, and record and list programs while the 9825 is performing other operations.
A few more exciting features of this
new calculator: Multidimensional arrays
(continued on second page)

New fully automatic LCR meter measures inductance, capacitance, and resistance over wider range

New multi-family Logic Probe has built-in pulse memory, low price

New calculator/controller with outstanding interface capability
(continued from first page)

Measurements of capacitors, inductors and resistors have been speeded up to rates as high as one reading per second with HP's new 4261 A LCR Meter. Autoranging and automatic selection of measurement equivalent circuits in CID, L/ D and R modes makes the 4261 A LCR meter ideal for testing components used in electronic equipment ranging from stereophonic gear to lab-grade test instrumentation.
Applications such as the measur~ ment of stray capacitance of cables, printed circuit board materials and other components become routine with the 4261 A. To facilitate the wide variety of applications, the 4261A will be available with three options: BCD, remote control, and an interface for HP 9800 series calculators via the HP Interface Bus (HP-IB) (IEEE Standard 488-1975).
Capacitance measurement capability is in eight ranges from 0.1 pF to 19.00 mF. Inductance can be measured in seven ranges from 0.1 µ,H to 1900 henries; resistance in eight ranges from 1 milliohm to 19 megohms. Dissipation factors of Oto approximately 1.900 can be made with the 4261 A. Measurements are made at 1 kHz for general applications and at 120 Hz for electrolytic capacitors. Accuracy is typically 0.2% of reading.
For details, check Don the HP Reply Card.
Automatic measurement is now possible for the parameters of semiconductors, pulse transformers , filter coils, electrolytic and film capacitors, or to determine the internal resistance of a dry cell or an electrolysis liquid .

Easy-to-use, simple, and rugged , the probe provides a highly effective solution to digital troubleshooting problems.
Troubleshooting of mixed logic families is now faster and more economical than ever before, thanks to HP's new 545A multi-family Logic Probe.
At the flick of a sw itch, the HP 545A Logic Probe changes to test most positive logic families including TTL and CMOS. An unambiguous single lamp display in the probe tip quickl y indicates logic HIGH , LOW, bad level, pulses or pulse trains. Yet, this rugged overload-protected probe costs one-half the price of previous multi-family probes.
The 545A also has a separate built-in pulse memory with its own indicator lamp to catch those elusive pulses and transitions that occur when you're not there to watch. Use of the pulse memory in no way interferes with probe operation as there's an independent memory display circuit.
The 15µ,A/15pF input hardly loads your circuits, yet gives pulse train respo nse to 80 mHz for TTL , 40 mHz for CMOS, and pulse width response to 1Ons.
HP's versatile new "grabber" connectors are provided so you can power the probe using IC test clips, test pins, or you can connect to power pin s on an IC with little chance of shorting to an adjacent pin. The probe operates from a wide voltage range-3 to 18 Vdc-and in the TTL mode offers standard TTL logic thresholds over supply ran ges from 4.5 to 15 Vdc.
Circle B on the HP Reply Card for your 545A data sheet.

allow you to organize data logically, thus saving program space and execution time. Memory load and record allows you to suspend processing, store the complete contents of memory on tapeincl ud ing programs, data, and pointers-for contin~ation later on.
Direct memory access (OMA) is yours with input speeds up to 400,000 16-bit words per second. Memory is expandable in 8K bytes to 32K bytes. Each bidirectional tape cartridge can store 250K bytes with an average access time of 6 seconds.
Accuracy to 12 digits with a dynamic range of 10-99 to 1099 and an internal calculation range of 1o -S l l to 10511 provides you with outstanding arithmetica I ca pabi Iities.
Because of the 9825 's vectored priority interrupt capability, available in the Extended 1/0 ROM, the calculator can act as a controller for several instruments or peripherals which require attention at unpredictable rates or times. Besides being used as a controller for instrumentation systems, it can also be used for pilot process control applications, remote data collection and production control.
As a controller, the 9825 can handle up to 45 measuring instruments simultaneously through its three 1/0 slots.
Three optional interface cards are available: one for 16-bit parallel data, one for BCD devices, and a third-the HP-Interface Bus-for instruments that conform to IEEE Standard 488-1975.
Upper and lower case alphanumerics are now available on both the 32character LED display and the 16character thermal printer.
The 9825's high level programming language (HPL) offers you power and efficiency for handling complex formulas and equations. HPL handles subroutine nesting and flags, and allows 26 simple and 26 array variables.
With all this versatility and speed and weighing just 12 kg. (26 lbs), the 9825 can legitimately be considered a portable computer.
For your free copy of the 16-page 9825A
brochure, check 0 on the HP Reply
Card.
MEASUR EMEN'fECOMPUTATION' NEWS

Economical pulse generators for TTL, CMOS, ECL, and educational applications

Meeting the requirements of digital logic laboratories, these pulse generators are extremely flexible with panel controls designed for easy operation.

HP's broad family of high quality pulse generators includes a cost-effective pulser for every performance level and application. Model 8011 A, for example, is HP's lowest cost pulse generator. It's 16V amplitude and 20 MHz repetition rate are perfect for the requirements of CMOS and TTL logic design. The pulse burst option (001) helps you speed logic debugging by letting you rapidly generate a precise pulse burst just by dialing the desired length on thumbwheel switches. The 8011 A's low cost of ownership also makes it an ideal choice for education applications. The logical , easy-to-use panel control layout, and short circuit proof output minimize familiarization and down time-important benefits in student labs.
Models 80128 and 80138 are versatile, general-purpose units which pro-

vide you additional pulse parameter control for more complex testing applications. The 50 MHz, ± 1OV performance of these models is ideal for TTL and basic ECL applications. The 80128 is HP's lowest cost 50 Hz pulser with variable rise and fall times . The 80138 has fixed transition ti mes less than 3. 5 ns

and also provides simultaneous positive and negative outputs useful in analog applications.
For literature, check L on the HP Reply Card.

Precision Constant Current sources give output useful to microampere region

Precision performance, low price, small size, and light weight combine to make these supplies useful as general purpose laboratory constant current sources for semiconductor circuit development and component evaluation.
MEASUREMEN'fECOMPUTAT/ON' NEWS

With a constant current source in the lab, you can:
· Evaluate reverse breakdown and forward V-1 characteristics of PN junctions
· Measure silicon wafer resistivity and contact resistance
· Test relays, meters, potentiometers, and electrolytic capacitors
· Aid in coulometric titration and precision electroplating
· Determine dynamic and incremental impedance of devices
HP constant current sources supply precisely-regulated (30 ppm) de current. Three models cover a range of ratings from 1 µ,A to 0.5A.
You can adjust the constant current output with the high resolution (0.02%) front panel control, or you can program the output current anywhere over an

entire range with an external voltage or resistance. The maximum voltage compliance can also be set with a voltage limit control or by external programming.
These supplies have no output capacitor. Output capacitance is minimized to reduce stored energy at the high impedance output, which along with specialized circuitry, reduces current transients in rapidly changing loads.
A separate monitoring terminal allows external voltage measurement without degrading constant current performance.
For technical data sheet, check J on
the HP Reply Card.

The "Time Standard" Company offers a wide choice of proven precision frequency standards
Hewlett-Packard frequency/time
standards in the HP Measurement
Standards Lab in Santa Clara, Calif. contribute timekeeping data regularly to both the U.S. Naval Observatory and the U.S. Bureau
of Standards.

As a leading manufacturer of cesium, rudibium and quartz standards, we at Hewlett-Packard offer you 35 years of frequency standards experience to help you make an optimum choice.
We can be of special help since many of our several thousands of frequency standards in the field are used in the most reliability demanding areas. These include LORAN C and OMEGA navigation, space vehicle tracking and guidance, satellite communication and basic timekeeping in numerous standards labs and observatories throughout the world.
One of the following precision frequency standards should meet your applications needs.
HP 5061A Cesium Standard
· Primary frequency standard with 7x10- 12 accuracy (with high performance tube, 0° to 50°C)
· Proven reliability (MTBF in excess of 40,000 hours) Your best choice for superior
performance and reliability.
HP 5062C Cesium Standard
· Primary frequency standard with 3x10- 11 accuracy (-28° to +65°C)
· Fast warmup (20 min. at -28°C) · Rugged construction (passed
400 lb. hammer blow test) Your best choice for harsh environments such as mobile naviga-

tion and communications systems.
HP 5065A Rubidium Standard
· Compact and light weight · Long term stability less than
1x1 o- 111month
· Short term stability less than 5x10- 13, 100 sec. averaging Your best choice for a secondary
atomic standard at a considerably lower price.
HP 105NB Quartz Oscillator
· High performance economical frequency standard
· Excellent short term stability and spectral purity
o- · Aging rate less than 5x1 10/day
Your best choice when excellent stability and versatility are needed at lowest cost.
HP 10544A Ovenized Component Oscillator
· Fast warmup · Excellent aging rate at low cost (less
than 5X 10- 10/day) · Rugged, compact, reliable
Your best choice for integrating into test and measurement equipment or communication and navigation systems.
For data sheets on all of these instruments, please check Fon the HP Reply Card.

New Application Note for Low Input Current, High Gain Isolators
Optically coupled isolators are usefu , in applications where large common mode signals are encountered. Examples are: line receivers, logic isolation, power lines, medical equipment and telephone lines. This Application Note 951-1 has at least one example in each of these areas for the 5082-4370 series high CTR isolators.
HP's 5082-4370 series isolators contain a high gain, high speed photodetector that provides a minimum current · transfer ratio (CTR) of 300% at input currents of 1.6 mA for the -4370 and 400% at 0.5 mA for the -4371. The excel lent low input current CTR enables these devices to be used in applications where low power consumption is required and those applications that do not provide sufficient input current for other isolators. For your free copy, check Q on the HP Reply Card.
HP offers new monolithic LED chips for watch industr~
The HP 5082-7800 series are common cathode monolithic chips designed for hybrid applications. Chips are available in seven segment, nine segment, and one digit fonts. Colons are available in discrete or monolithic form.
Four character sizes with a common cathode are available: 53 mil, 80 mil, 100 mil and 120 mil. These are easy to read, MOS compatible and offer an excellent aesthetic appearance.
The chips are packaged on vinyl film or in waffle packages. For detailed specific technical data, check I on the HP .Reply Card.
New low power chips are 100% electrically tested, before shipment, to a high HP standard criteria.

MEASUREMENrJll;OMPUTATION: NEWS

comPonenT · ~...

'

-

~v

.

.

New Metal-InsulatorSemiconductor capacitors for microwave IC's

Low VF Schottky mixer diodes for better matching and lower noise

Insertion loss reduced by 20°/o in new SPST microwave switches

Magnified view of new MIS chip capacitor with oxide-nitride insulator yielding superior reliability.
These new 5082-0900 MIS chip capacitors have been designed for shunt rf bypassing and series de blocking in amplifiers, osc;illators, switches, limiters, mixers and modulators.
Eleven units are offered in the 0.5 to 45 pF range. Capacitance tolerance is ±15%. Tolerances to ±5% and values in the 45 to 100 pF range are available on special order. Minimum breakdown voltage for units from 0.5 to 2.0 pF is 250 V; 5.0 to 15 pF-150V; units from 20 to 45 pF-100 volts.
In the MIS structure, the metal is gold, the insulator is silicon nitride over silicon dioxide, and the semiconductor material is silicon.

Low forward-voltage equivalents of HP's microwave Schottky diode line are now available. A rating of 200 to 300 millivolts forward drop versus the conventional millivolt droppage of 400 to 500 millivolts is now available in a total of 23 devices including chips, beam leads and quad configurations.
Intended primaril y for mixer applications, the low VF diodes are closer to a 50 ohm impedance than standard Schottky mixer diodes, resulting in lower VSWR over the band. At lower levels of l.o. power, the impedance is equivalent to standard units, a property useful in starved local osci llator mixers.
This new forward voltage rating applies to the following series of components:
5082-2229 beam lead mixer diodes 5082-2231 hermetic microstrip quads 5082-2271 broadband microstrip quads 5082-2285 hermetic si ngle chip
coax packages 5082-2765 hermetic single chip
microstrip packages 5082-2774 broadband single chip
microstrip packages
For data sheets describing the above products, check Hon the HP Reply Card.

These SPST switches ·use PIN diodes in shunt across a 50 ohm transmission line. Control current for the 33132N33632A is 30 mA for the 33134N33634A is 200 mA.
Two new SPST microwave switches reduce insertion loss in X-Band and KuBand by 20% over currently available types. The HP 33130 series are complete switches, with RF connector, bias circuits, and built-in de returns . Model 33 l 32A is a complete 2-diode switch with insertion loss of 1.8 dB max from 12.0 to 18.0 GHz.
The Model 33 l 34A is a complete 4-diode switch with insertion loss of 2.3 dB maximum over the same frequency range.
The basis of the HP SPST switch product line is the coaxial module. The 33600 series module is optimized for low insertion loss with high isolation. The modules are available with either two or four diodes. Three diode units are available on special order.

For a technical data sheet, check G on the HP Reply Card.
MEASUREMEN'fECOMPUTATION: NEWS

Noise figure of low VF diodes is typically less than 6 dB at 9 GHz for power levels ranging from - 5 dBm to + 5 dBm.

For a technical data sheet on the 33 730 and 33630 Series switches, check P on the HP Repl y Card .

A new ultra-low distortion analyzer gives you readings to -90 dB

The Hewlett-Packard 4333A Distortion Analyzer measures total harmonic distortion down to 0.01 % full scale at 41 spot frequencies, each variable over a range of more than ± 8%.
The new 4333A gives you ±3 % accuracy over its entire 10 Hz to 100 kHz range .
The 4333A is easy to use. Automatic fundamental nulling reduces critical manual nulling operations. Select your measurement range in 10 dB steps and read distortion directly on the large, clearly marked panel meter. A front-

panel monitor output lets you conveniently analyze the harmonic distortion using a scope or recorder.
A high sensitivity voltmeter mode offers 13 ranges in 10 dB steps; range is from 100 µ, V to 100 V rms ful I scale.
When you need believable amplifier or oscillator distortion measurements, rely on the 4333A.
For more information , check E on the HP Reply Card.

New distortion analyzer with distortion input sensitivity of 1 Vrms for 100% set level reference.

lnkless writing for HP strip chart recorders

New thermal writing option produces a crisp, uniform trace.

For the first time, thermal writing is available for a series of HewlettPackard strip-chart recorders . Models 7130A and 7131 A, one and two-pen , 10-inch OEM recorders can be equipped with thermal writing pens and event markers for long-term, unattended operation. Models 7132A and 7133A, laboratory version s, can be similarly equipped.
Each thermal tip contains a tenwerature sensing element used to maintain a constant tip temperature. The tip

temperature is therefore independent of ambient temperature, paper speed, etc.
Designated Option 054, the inkless system includes beryllium-tipped pens designed to last the lifetime of the instrument. Recordings are of high contrast and are easy to read .
For more details, check K on the HP Repl y Card.

New Application Note helps match microwave frequency counters to measurement requirements

At one time there weren't many microwave frequency counters from which to choose. Now, there are a variety of these counters available with varying degrees of sophistication in design and measurement capability. The new Hewlett-Packard Application Note 144, "Understanding Microwave Frequency Measurement" discusses tradeoffs between microwave frequency counter designs which merit consideration when choosing a counter for a particular application.
The Application Note discusses in detail considerations of measurement

speed, accuracy, dynamic range, and tolerance to modulations and unwanted noise on the signal for each of the three common down-conversion techniques: prescale, heterodyne, and transfer oscillator. It also suggests other useful considerations such as input characteristics , sensitivity, and input/output structure.
The booklet should prove useful to the microwave.engineer in selecting a frequency counter to meet his needs.
For your free cop y of this Application Note, check N on the HP Repl y Card.

The successful 5340A Frequency Counter represents one of several designs described in the new AN 144, " Understanding Microwave Frequency Measurement" .
MEASUREMENrJlCOMPUTATION: NEWS

HP high resolution CRT displays for OEM applications
The CRTs in these displays have a totally new design, optimized exclusively for information display and to reproduce fine image detail with superior contrast and uniformity.

Stable light output for long scan periods permits time exposure photograph to paint a picture of body temperature versus location in a medical thermography application.
Hewlett-Packard's Models 1332A, 1333A, and 1335A CRT displays are designed to provide excellent images in all types of OEM systems. Applications for these displays include spectrum, network and chemical analyzers, nuclear medicine, medical thermographic ultrasound, and automatic test systems, among others.
Model 1332A is designed for the OEM that has both visual and some photographic requirements. CRT display parameters are optimized for such a combined application including large 9.6x 11.9 cm viewing area. Display brightness is such that it can be viewed in high ambient light conditions while maintaining resolution and gray shades for photographic work.
MEASUREMENrHCOMPUTATIDN,NEWS

The 1333A CRT is optimized for photographic image quality with a wide range of gray shades, contrast, and uniformity as shown in this high resolution gamma camera brain scan.
Model 1333A is designed specifically for applications in which photographic recording of displays is the major factor. The smal I spot size of 0.20 mm offers exceptional image quality that makes evaluation of photographs easier and more accurate. A specified light output uniformity assures that the display information is an accurate representation of the input signals. The high resolution CRT display qualities make the 1333A ideal for recording rapid sequence dynamic studies in nuclear medicine and for capturing transient displays in ultrasound work. The Bx 10 cm screen can be reproduced on Polaroid® film with very little optic reduction which al lows the use of al most 1:1 optics and minimizes design difficulties encountered when using enlarging or reducing optics.

Fine image detail and a well-focused spot at all intensity levels make the 1335A ideal for use in Spectrum, Fourier, Network, and Chemical analysis as well as automatic test systems.
For applications requiring variable persistence and storage, the 1335A offers exceptional uniformity needed in OEM medical and instrumentation systems. The variable persistence mode can be used to eliminate flicker on some presentations with the ability to increase persistence to match the refresh rate. In the storage mode, resolution is over 20 lines per cm (50 lines per in.) permitting the retention of sharp detai Is. For maximum flexibility, any operating mode-erase, store, write, conventional, or variable persistence-can be selected with manual front panel controls, remote program inputs, or a combination of both.
For detailed specifications on these CRT displays, Check Con the HP Reply Card.

Buy the HP-65 now* and get $195 worth of proven software FREE

During this special promotion, purchasers of Hewlett-Packard's HP-65 fully programmable pocket calculator will receive FREE with the calculator, a $195 coupon for the delivery of 4 Application Pacs and 5 Users' Library Programs of their choice. The promotion runs through April 30, 1976.
There are 14 Application Pacs currently available in electrical engineering, finance, mathematics, statistics, medicine, navigation, aviation, surveying, machine design, stress analysis and chemical engineering. You may choose any four of these Pacs, each containing up to 40 pre-recorded programs from that particular discipline.
In addition, each purchaser will be able to choose five of 15 popular programs from the HP-65 Users' Library of contributed programs. Each of these programs includes a complete keystroke Iisting, user instructions and supporting documentation. The entire library listing, available to HP-65 owners, contains more than 4000 contributed programs.
Software is the difference that sets our HP-65 Fully Programmable apart from all other calculators. This hardware/software combination permits the HP-65 to remain the most versatile hand-held computing system available. Like a computer, the HP-65 memorizes programs of any size that are fed into

it on tiny magnetic cards, 100 program steps to a card. With just a few keystrokes by the user, it executes the program and gives the answer to complex problems with an accuracy of up to 10 digits. Five User Definable keys plus 51 preprogrammed functions and operations plus a superior editing capability add up to "a great deal ".
Call , toll-free, 800-538-7922 (in Calif. 800-662-9862) for an HP dealer near you so that you can take advantage of this special $195 software offer before April 30, 1976.
For descriptive literature only, check A on the HP Repl y Card.

·Offer valid until April 30, 1976 in continental U.S.A., Alaska and Hawaii.

'"i...b-~-i-i·f-=i·i~F-
-~~
Ciili:rz±
·"!!!il'l;.,"9!"
@Btf±

a~-
w-r· NHl"M.fTT·MOl#ID
---
-~
¥±1M'

East-4 Choke Cherry Road, Rockvi lie, MD 20850 Ph. (301) 948-6370.
South-P.0. Box 28234, Atla nta, GA 30328, Ph. (404) 434-4000.
Midwest-5500 Howard Street, Skokie, IL 60076, Ph. (3 12) 677-0400.
West- 3939 Lankershim Blvd, North Hollywood,CA 91604, Ph. (213) 877-1282.
Europe-P.0. Box 349, CH-121 7 Meyrin 1, Geneva, Switzerland, Ph. (022) 41 54 00.
Canada-6877 Goreway Drive, Mississauga, Ontario, L4V 1l9, Ph. (416) 678-9430.
Japan-Yokogawa·Hewlett-Packard Ltd., Ohashi Bldg., 59-1 Yoyogi, 1-chome, Shibuya·ku, Tokyo 151 , Ph. 03-370-228 1192.
00682

Ht oepreu'tsaa ms ii·mcrpolperwoaceyssor

in your product.

.

This is what you'll work with if you buy one of Pro-Log's dedicated control elements with the microprocessor already built in.

Buy a dedicated control element, for all practical purposes a black box, with a microprocessor already bullt In.
We've developed subsystems using microprocessors. They come in modular configurations readily expandable to meet your product requirements. You hardwire them directly to relay contacts, switches, push buttons , displays or other real-world devices . They give you all the capabilities of a microprocessor with none of the headaches. And we deliver them in a matter of weeks.
When you use our subsystems, we give you the kind of production and documentation assistance that results in a product your present manufacturing people can build and your present service force can support.
And system design stays with the design engineer.
Plus, we give you something more, a free set of plans and a second source.
Order 250 subsystems and we'll throw in free non-exclusive manufacturing rights and a complete set of manufacturing and assembly plans allowing you to build your own hardware, relying on us as an established and dependable second source.
We make everything you need to design with microprocessors.
Our starter sets include a microprocessor subsystem, a Series 90 PROM programer, a microprocessor system analyzer, plus all associated hardware . 4-bit sets cost around $3,000, 8-bit sets around $3,500, a substantial savings over what you'd pay if you purchased all these items separately.
ELECTRON IC D ESIGN 7, March 29, 1976

We have education too. Our half-day introductory seminar takes
a hard look at the function of microprocessors in real-world applications.
Our three-day hands-on design course teaches engineers how to formulate , program and use microprocessor modules.

Our free booklet, "The Microprocessor User's Gulde" answers all your questions.
It explains what a microprocessor is, what it's capable of doing , what criteria you need to evaluate the ones on the market and how Pro-Log can help you put them to best use. Write for your copy.

To show how much Pro-Log can save you both in time and money, consider this . We've got a one-card 4004-based system called the PLS-401A. It includes a microprocessor; crystal controlled clock; 16 lines of TTL input; 16 lines of TTL output; sockets for 1024 words of program memory; 80character RAM and built-in power-on reset. It costs only $99 in quantities above 500 ($175 in quantities of 10.) How long would it take , and what would it cost you to design and build something in-house that could do the same job?
And this is just one example of the many microprocessor subsystems we offer using 4004, 4040, 8008, 8080, and 6800 microprocessors.

PRO-LOG CORPORATION 2411 Garden Road Monterey, CA 93940 Telephone (408) 372-4593 TWX 910-360-7082
CIRCLE NUMBER 7
19

Even the best equipment budget can

REI stocks over 8,000 fully checked-out

only go so far. And at the price you pay for

test instruments, and they're ready whenever

electronic test equipment nowadays, that's not you are. For the full story on renting, as well as

very far at all.

our low prices, send in the coupon for prompt

Unless you rent your equipment from delivery of our free illustrated catalog ... or call

REI.

us now for your immediate requirements.

When you rent from us, there's no large

cash outlay. You pay only for the time you have r-iwntru~~trorucs,In;---------i

I your instruments, and you return them when

99 Hartwell Avenue, Lexington, Mass. 02173

you're through. So you never have to spend your money on idle equipment.
Getting more for your money is just one reason for renting from REI. Immediate de-

I I I

Please send me your free instrument renW catruog:

Name Company

Title

I I I I

I livery is another. We have over $10 million in
inventory in fully stocked centers around the country. And, when you have short-term needs,

Address _ _ _ _ _ _ _ _ _ _ _ _ _ __

City

State

Zip

:

L you can rent equipment for just as long as you
need it, and make it pay for itself.

Tel.Number _ _ _ _ _ _ _ _ _ _ _J

Rental Electronlcs, Inc. <®

A P-EPSICQ LEASING COMPANY
Burlington, MA (617) 273-2770 ·Gaithersburg, MD (301) 948-0620 ·Oakland, NJ (201) 337-3757 · Ft. Lauderdale, FL (305\ 771-3500 ·Des Plaines, IL (312) 827-6670 ·Dallas, TX (214) 661-8082 ·Mountain View, CA (415) 968-8845 ·Anaheim, CA (714) 879-0561 · Rexdale, Ontario (PLC Leasing Ltd.) (416) 677-7513

See us at Booth #2702 at Electro 76 May 11-14 Bicentennial IEEE Show in Boston

CIRCLE NUMBER 8

c
MARCH 29, 1976

(500 quantities) ; the microNova CPU/4k single-board minicomputer wiith 4-k words of memory costs $950 (single quantities ) .
CIRCLE NO. 319

Data General's µP-based mini extends its Nova line

A downward-compatible minicomputer system based on a 16-bit microprocessor has been announced by Data General. Known as the microNova family, the system is available as a full minicomputer, a single central-processing-unit board with 4-k words of memory or as individual CPU, memory and support chips.
"An original-equipment manufacturer can start out with a fully packaged microNova minicomputer, then integrate downward into microNova boards or chips as his development time or product volume allow, without having to redesign hardware or software," says Engineer.ing Vice President Carl Carman.
Since the microNova is completely software-compatible with the company's line of Nova m1mcomputers an extensive library of software already exists to support the new family.
Included among major competitors who have introduced their own compatible families of µCs through full minicomputers are Digital Equipment Corp., with the LSI-11; Texas Instruments with the 990 Series. Of course, there are several suppliers of monolithic 16-bit MOS chips-notably General Instrument and National Semiconductor.
"In a way, each of these products can satisfy a part of the market," says Data General's Herb Richman, "but in other ways they fall short because they're lacking in product-line breadth, software or other forms of support."
All of the microNova chips are produced by Data General at its plant in Sunnyvale, CA. The CPU has common address and data pins and is designed for use with the company's 20-pin dynamic RAMs. Separate refresh circuitry is not required by the CPU because it has an integral refresh cyde.

The microNova family consists of chip set, board computer and fully packaged minicomputer.
There are two separate serial I/O lines on the chip and a realtime clock. Other chips available to complete the system are an I/ 0 controller to decode a 16-Mb/s data stream for communication with peripheral devices, address-buffer elements, data-line buffers and memory-sense amplifier/ buffer chips.
The microNova minicomputer is available fully packaged with a separate calculator-like control panel attached to the main unit by a long flexible cable. Nine-slot and 18-slot versions, each slot having 32-k memory capacity, allow plenty of program storage.
In a complete system including the microNova minicompu:ter, diskette and ASCII terminal, development software is available at no extra cost.
Software such as a disc operating system, text editor, Fortran IV compiler, ass em b 1er, relocatable loader and symbolic debugger provide complete support for developing anything from a fully customized system to a dedicated system using the chip set.
The CPU chip mN601 sells for $225 (single quantities ) and $95

Listen to the sound: the part is corroding
It used to be that listening to corrosion was like watching grass grow. A sensitive electronic listening device can now tune in on corrosion and catch it red-handed. The computer controlled instrument can locate and measure corrosion deep within the bowels of a piece of machinery, inside the wing of an aircraft or even inside an integrated circuit package.
"We look at it as an acoustic previewing of failures," says Allen Green, general manager of Acoustic Emission Technology Corp. in Sacramento, CA. Corrosion: is a chemical reaction that usually gives off a minute amount of hydrogen gas. The gas bubbles off like boiling water. The bubbling action gives off a very small level of sound that can be detected in the 100-kHz to 2-MHz window in the ultrasonic spectrum. By listening with an extremely sensitive receiver to the acoustic energy in that portion of the spectrum, corrosion can be detected in a nondestructive way before a failure occurs.
A single piezoelectric sensor is first placed on the item of interest. The signal from the sensor is connected to a preamplifier with an rms noise threshold of aibout 800 nV, then filtered so specific octavewide bands of frequencies are looked at individually.
When a sound is detected, additional sensors are placed on the item of interest and readings are taken by each. An LSI-2 computer from Computer Automation, Irvine, CA, analyzes the data from the sensors and, by triangulation, calculates the exact position of the corrosion.
If the signail is too small for an accurate reading, the part can be heated. Green notes that a 10 to 18-F increase in temperature doubles the reaction rate of the corrosion and, therefore, also doubles the level of the sound given off.
When multiple sensors are used the propagation of the reaction

ELECTRONIC D ESIGN 7, March 29, 1976

21

can be plotted by the computer as a function of time.
Lockheed-California Co. in Burbank, CA, is using the equipment for structural analysis of aircraft.
The equipment can detect micrograms of loose material inside integrated circuit packages, Green says. He notes that the technique has been used to find the cause of failures where X-rays and other methods failed.
An improved Schottky diode tests for ozone
Chemical elements that are believed to be responsible for depleting the earth's atmospheric ozone layer can now be detected more precisely using an improved Schottky-barrier diode.
These chemicals in the stratosphere signal their presence by emitting electromagnetic radiation of very precisely defined frequencies (in the 115-to-118-GHz and 183-to-184-GHz ranges).
The improved, low-noise diode developed by Dr. Robert Mattauch, Associate Professor of Electrical Engineering at the University of Virginia, Charlottesville, VA, is used as a millimeter-wave mixer in a sensitive receiver to detect these frequencies.
Tests to measure trace gases like N 20 and ozone have already been conducted by sensi.tive receivers in aircraft using these new diodes up to 40,000 ft. More tests are scheduled for June.
The diodes, measuring only 10-4 in. in diameter, are formed on a single gallium arsenide chip 5 X 10 mils in area and 5 mils thick. The small size of the diodes allows a large number of them to be placed on a single chip, although only one of them is actually used :as the mixer.
Color-TV picture tube is better and cheaper
A color-TV picture tube that can be manufactured by a fully auto~ mated facility has been developed by Zenith Radio and Corning Glass. The tube will cost 20 % less to produce and have improved performance.
22

The tube is built with a deflection angle of 100°, which "provides a desirable combination of styling, power consumption and picture quali·ty advantages," according to Joseph P. Fiore, Zenith's vice president of manufacturing and co-inventor of the Chromacolor picture tube.
The depth of the tube was reduced 2-1/2 in. Resolution was improved by using a smaller electronb ea m spot size. And power consumption was held down because the 100 ° tube uses the same deflection-drive power components used in a 90 ° .unit.
The tube is built with a striped, negative-guard-band phosphor screen. A slot-aperture mask assembly designed by Zenith engineers reduces mask weight by over 2 lb and eliminates the glass skirt around the edge of the faceplate. The aperture mask is held rigid by studs in the four corners of the faceplate panel.
Multistage mask-forming dies are used to accomplish a stable, self-supporting mask that eliminates the conventional frame.
Mask-mounting studs may be precision-located and cemented to the inside face of the tube by an automated process said to be simpler than the stud-mounting and alignment system currently used.
The same mounting studs may be used for automatic precision alignment of the faceplate to the funnel. That eliminates the requirement for precision alignment fix!tures now used during the tube-sealing operation. The technique is said to increase alignment accuracy and improve production yields.
The mask is built with an integral electron shield to protect the screen from stray or overscanned electrons. This eliminates the need for a separate shield.
"One of the most important features of the design," Fiore adds, "is the ease of mask insertion and removal. Automation of these operations is now possible using simple equipment."
Zenith is banking on the new picture tube to remain competitive with foreign set makers, which have doubled their share of the market in the past four years.
The company plans to manufacture about 200,000 of the tubes this year.

Army opens $40-million missile flight simulator
A complex of simulators that can recreate virtually any man-made or natural phenomena that a missile might encounter in flight has been opened at the Army's Redstone Arsenal, Huntsville, AL. The $40-million facility will be used by all branches of the military and their contractors in the design, development and evaluation of missile systems. It will also provide a tool for analyzing foreign weapons.
The three-story, 75,000 ft2 Advanced Simulation Center consists of three environmental simulation systems (infrared, electro-optical and radio frequency) and a hybrid computer complex to tie them t~ gether.
The center enables a designer to test sensors, guidance-and-control components and flight hardware. Simulations are performed across a wide frequency spectrum, from near ultraviolet through microwave, with expansion capabilities inherent in the design.
One simulator accommodates missiles with sensor systems operating in both the 0.2 to 0.4 and 1.0 to 5.0-micron bands. The sensors are controlled by a hybrid computer in six degrees-of-freedom while the target is being acquired.
The gimballed flight table provides pitch, yaw and roll movements to the sensor airframe. A target generator simulates a variety of target background combinations, including tailpipes, plumes, flares and fuselages in single or multiple displays against clear, clouded, overcast or sunlit skies.
These combinations are then displayed in azimuth, elevation, range and aspect by the target projection subsystem through a folded optical network, a display arm and a display mirror. Simulation capability ranges from open1oop component evaluation to closed-loop total-system simulation.
"Millions of dollars each year will be saved in research and development and actual flight tests," according to an Army spokesman. The center will also reduce significantly the time and manpower required to develop a missile system.
ELECTRONIC DESIGN 7. March 29. 1976

PACKAGING/SWITCHES/READERS
1441 East Chestnut Avenue, Santa Ana, CaliforniJ 92701 Phone 714/835-6000
Also stocked and serviced in North America by G. 5. Marshall, R-A-E, Zentronics.
CIRCLE NUMBER 9

Ceralani Chips. en you're on the
outside loo · gm· .

If you're looking at ways to put more capacitance into a microcircuit, look into Ceralam chips. Because they're ceramic, they have the volumetric efficiency necessary for microcircuit applications. So you can package a lot of capacitance. Even when you're short on space.
Because they're made by the leader in multilayer technology, AVX chips deliver the performance needed in your

most demanding applications. They're tested for physical, electrical, environmental characteristics repeatedly during production. Qualified to AVX's demanding specifications. So you can adhere to yours.
Ceralam chips also make bonding easy. They're available in a variety of terminating materials, so you won't have to introduce changes into existing designs. And they

can be supplied with special terminations. Like AVX's exclusive alloy NiGuard®. A material that eliminates the need for preforms and wire bonding. And prevents base metal bleed through and silver migration.
If you've been looking around for the right kind of capacitors for your microcircuit designs, settle on Ceralam chips. They'll make an insider out of you.

/~\Vb:<:Thelnsiders

AVX Ceramics, P.O. Box 867, Myrtle Beach, SC 29577 (803) 448-3191 TWX: 810-661-2252 Olean, NY {716) 372-6611 TWX: 510-245-2815
Specifications i
10 physical sizes / Capacitance Range:
1pf to 1.5 mfd ' Voltages:
100, 50,25 Three temperature
characteristics Four available I terminations /j

AVX Distributors: Cramer Electronics, Inc./Elmar-Liberty Electronics Jaco Electronics, Inc. /Newark Electronics/Texas Instrument Supply

CIRCLE NUMBER 1O

24

ELECTRONIC DESIGN 7, March 29, 1976

Motorola Turns On 4K RAM Availability
We keep hearing of 4K RAM delivery problems, particularly with popular 16-pin types. Well, forget that. With Motorola's totally turned-on 4K RAM production at the Austin, Texas facility, availability is the word for
4Ks. Availability of the 16-pin MCM6604 and the 22-pin MCM6605A. Let Motorola eliminate the 4K RAM hassle for you, today and with inflation beating low prices, at that.

MCM6604THE 16-PIN 4K
Three speeds to choose from · Recognized industry standard · Directly replaces 2104, MK4096,
4096,84096 · Small package optimizes system density

MCM6605A - THE 22-PIN 4K
· 2.5 mW standby . . . Ideal for battery backup · Three speed choices - down to 150 ns · Alternate sourced by IM7505 Series · Documented Reliability - Ask us for a copy
Motorola Semiconductor Products Inc .. MOS Memory Marketing, 3501 Ed Bluestein Avenue, Austin, Texas 78721

COME AND GET 'EM...FROM THESE AUTHORIZED MOTOROLA DISTRIBUTORS

ALABAMA, Huntsville

.... . Hall-Mark Electronics

.... (205) 837-8700

ALABAMA, Huntsville ·........... ·. Hamilton / Avnet Electronics . ... ..... (205) 533-1170

ARIZONA, Phoenix

........ Hamilton / Avnet Electronlcs . . .... (602) 275-7851

ARIZONA, Phoenix .............. .Liberty Electronics/ Arizona .

. .{602) 257-1272

CALIFORNIA, El Segundo

.. Liberty Electronics Corp. .

. .(213) 322-8100

CALIFORNIA, Irvine ..

. .Cramer/ Los Angeles ....

. ... (213) 771-8300

CALIFORNIA, Los Angeles

Hamilton Electro Sales . . ........ (213) 558-2121

CALIFORNIA, Mountain View ...... Elmar Electronics, Inc.

. .... (415) 961-3611

CALIFORNIA, Mountain View ...... Hamilton / Avnet Electronics ......... (415) 961-7000

CALIFORNIA, San Diego .

. Hamilton/ Avnet Electronics ......... (71 4) 279-2421

CALIFORNIA, San Diego .......... Liberty Electronics / San Diego ..... (714) 565-9171

CALIFORNIA, Su nnyvale

... Cramer/ San Francisco ........... . . (408) 739-3011

COLORADO , Comm erce City . ...... Elmar Electronics, Inc.............. (303) 267-9611

COLORADO, Denve r .............. Hamillon / Avnet Electronics . . .. ... . {303) 534-1212

CONNECTICUT, Danbury . . ..... Schweber Electronics .......

. . (203) 792-3500

CONNECTICUT, Geo rgetown . ... . . Hamilton/ Avnet Electronics . . ... (203) 762-0361

CONNECTICUT, North Haven .... Cramer/ Con necticut

........ (203) 239-5641

FLORIDA, Hollywood

.... Hamilton / Avnet Electronics ......... (305) 925-5401

FLORIDA, Hollywood ............. Schweber Electronics

. .... (305) 927-0511

FLORIDA, Orlando .......... . . . .Cramer / Orlando

. . . . . . . . . . . (305) 694-1511

GEORGIA, Atlanta . . ............ Cramer / Atlanta . . . . . . . . . . . . . ... (404) 446-9050

GEORGIA, Norcross .

. . Hamilton / Avnet Electronics . ..... ... (404} 446-0800

ILLINOIS, Chicago . . .

. ... Newark Electronics Corp. . ......... (312) 638-4411

ILLINOIS, Chicago ..... ........... Semiconductor Specialists, Inc. . . (312) 279-1000

ILLINOIS, Elk Grove Village

... Schweber Electronics

.. (312} 593-2740

ILLINOIS, Mt. Prospect

.. Cramer/ Chicago

...... (312) 593-8230

ILLINOIS, Schiller Park ............ Hamilton / Avnet Electronics . . . . . . (312) 676-631 o

INDIANA, Indianapolis ............ Graham Electronics Supply, Inc...... (317) 634-8202

INOIANA, Indianapolis

..... Pioneer / Indianapolis ............. (317) 849-7300

KANSAS, Lenexa .

. .... Hall -Mark Electronics

.... (913) 666-4747

KANSAS, Lenexa .....

. ... Hamilton / Avnet Electronics ......... {913) 686-8900

MARYLAND, Rockville .......... . . Cramer / Washington ....... . ....... (301) 946-0110

MARYLAND, Gaithersburg ......... Pioneer/ Washington Electronics . . . (301) 946-0710

MARYLAND, Hanover .

. ...... Hamilton/ Avnet Electronics .

. . {30 1) 796-5000

MARYLAND, Rockville

.. ... Schweber Electronics . . . . . ..... (301) 661-3300

MARYLAND, Savage .............. Pyttronic Industries, Inc .. . ........ (301) 792-7000

MASSACHUSETTS, Burlington

. Hamilton / Avnet Electronics ......... (617) 273-2120

MASSACHUSETTS, Lexington ..... Harvey Electronics .......... .. .... (617) 661-9200

MASSACHUSETTS, Newton Centre .. Cramer Electronics, Inc.

. .. (617) 969-7700

MASSACHUSETTS, Waltham

. Schweber Electronics .

. ... (617) 690-6464

MICHIGAN , Detroit ............... RS Electronics . . . . . . . . . · . . ..... {313) 491-1012

MICHIGAN, Livonia .

. ........ Hamilton / Avnet Electronics ....... _. (313) 522-4700

MICHIGAN, Livonia .............. Pioneer/ Detroit

.. (313) 525-1800

MINNESOTA, Eden Prairie ......... Schweber Electronic s .............. (612) 941-5200

MINNESOTA, Edina .

. ...... Cramer/ Minneapolis

........ (612) 635-7611

MINNESOTA, Edina ....

. ...... Hamilton / Avnet Electronics ........ (612) 941-3801

MISSOURI, Hazelwood .

. ...... Hamilton / Avnet Electronic s ......... (314) 731-1144

MISSOURI, St. Louis .............. Hall-Ma rk Electronics . . . . . . ..... (314) 291·5350

NEW JERSEY, Cedar Grove

Hamilton / Avnet Electronics ........ .(201) 239-0600

NEW JERSEY, Cherry Hill . . .... Cramer / Pennsylvania

........ (609) 424-5993

NEW JERSEY, Mt. Laurel .......... Hamilton / Avnet Electron ics . . ... (609) 234-2133

NEW JERSEY, Moorestown

... Arrow Electronics .............. . (609) 235-1900

NEW JERSEY, Pennsauken .

. Radio Electric Service Co.

. ..... (609} 662-4000

NEW JERSEY, Saddle Brook . . . . . . Arrow Electronics

............ (201) 797-5800

NEW JERSEY, Somerset . . . . . ... Sch weber Elect ronics .............. (201) 469-6008

NEW MEXICO, Albuquerque . . ..... Hamilton / Avnet Electronics . . .... (505) 765-1500

NEW YORK, Farmingdale .

. .Arrow Electronics

.. (516) 694-6800

NEW YORK, Hauppauge, LI.

.. Cramer/ Long Island

....... (516) 231-5600

NEW YORK, Rochester

... Cramer/ Rochester

.... ....... (716) 275-0300

NEW YORK, Rocheste r ............ Hamilton / Avnet Electronics ......... (716) 442-7620

NEW YORK, Rochester

....... Schweber Electronics .

. . (7 16) 461-4000

NEW YORK , East Syracuse ..

. .. Cramer/ Syracuse .. .......... ..... (315) 437-6671

NEW YORK , East Syracuse .

. .. Hamilton / Avnet Erectronlcs . . . .. ... (315) 437·2642

NEW YORK, Westbury , L.I. ......... Hamillon / Avnet Electronics ....... {5 16) 333·5800

NEW YORK, Weslbury , L.L ......... Schweber Electronics .

. ... (516) 334-7474

NEW YORK , Woodbury , L.I.

. Harvey Electronics ................ (516) 921-6700

NORTH CAROLINA , Winston-Sale m . Cramer/ Win st on-Sale m ........... .(919) 725-871 1

OHIO, Beachwood .

. .... Schweber Electronics ........ . .. (2 16) 464·2970

OHIO, Cleveland

....... . Hamilton / Avnet Electronics ......... (2 16) 461-1400

OHIO, Cleveland ................. Pioneer-Standard Electronics. Inc... .(216) 587-3600

OHIO, Dayton .

. ..... Hamilton / Avnet Electronics ........ (513) 433·061 o

OHIO, Dayton .

Pioneer/ Dayton

..... .. . . (513) 236-99Ci0

OHIO, Solon .................... Cramer / Cleveland

.. (2 16) 248-6400

OKLAHOMA, Tul sa

Hall-Mark Electromcs .

(916) 635·8458

PENNSYLVAN IA, Philadelph ia

Pioneer/ Philadelphia

........ {215) 674-5710

PENNSYLVANIA, Pittsburgh .

Pioneer/ Pittsbu rgh

. (412) 762· 2300

SOUTH CAROLINA, Columbia ..... Dixie Radio Supply Company , Inc..... (803) 779-5332

TEXAS, Dallas

...... Hall-Mark Electronlcs Corp.

. ... (214) 231-6111

TEXAS , Dallas ................... Hamilton / Avnet Electron ics ......... {214) 661-8661

TEXAS, Dallas ................... Schweber Electroni cs ............. . (214) 661-5010

TEXAS, Dalla s

..... Sterling Electronics

. (214) 357-9131

TEXAS, El Paso

..... Midland Speciality Co .

. ... (915) 533-9555

TEXAS , Houston ........·· ·. ..... Hall -Mark Electronics .............. (713) 761 -6100

TEXAS, Houston ................. Hamilton / Avnet Electronics ..... .... (713) 526·4661

TEXAS , Hou ston

.Sterling Electronics, Inc.

. . (713) 627-9800

UTAH, Salt Lake City . . . . . . . . Cramer/ Utah ..................... (801) 487-4131

UTAH, Sall Lake City . . . . . . ....... Hamilton / Avnet Elec tronic s ......... (801) 262-8451

WASHINGTON, Bellevue

Hamilton / Avnet Electronics ........ (206) 746-6750

WASHINGTON, Seattle . . ....... Almac / Stroum Elec tronics .

. ... (206) 763·2300

WASHINGTON, Seattle .

. .... Liberty Electron ics Corp . . ........ (206) 763-8200

CANADA

CALGARY, T2E 6L7 . Alta .

Varah's

...........·· . , · . . (403) 276-8818

EDMONTON, Alla. .

Bowlek Elec tric

_. (403) 426-1072

LONDON , Ont.................... CM Peterson Co .. ltd.

. ... (519) 434-3204

MISSISSAUGA, Ont.

........ Hamil\on / Avnet ............. .. . . · (416) 677-7432

OTTAWA, Ont. . . . . . . . . . .

. . Zentronics . Lid.............··..... (613) 238-6411

OTTAWA, K2C 2B4, Ont.

..... Hamilton / Avnet lnt'I Ltd . . ....... (613) 226-1700

ST. LAURENT, P.O. H4S 1G2 . . . Hamilton / Avnet

........ (514) 331-6443

TORONTO, Ont. ............... . Zentronics, Ltd.

. .... (416) 787-1271

TOWN OF MOUNT ROYA L, P.O.

Zentronics, ltd.

. . (514) 735-5361

VAN COUVER, B.C.

Bowtek Electric ...... .... ....... (604) 736-1141

VANCOUVER , B.C................. Varah's

...· (604) 873-3211

WINNIPEG, Man.

. .. Bowtek Electric

.... (204) 786-7 52 1

ELECTRON IC D ESIGN 7, March 29, 1976

25

AT THE INTERNATIONAL SOLID-STATE CIRCUITS CONFERENCE
Dynamic RAMs reach 16-k density -and touch off a memory battle

"Users are being dragged kicking and screaming into the 16-k race without first getting really good 4-ks."
That statement was voiced by one participant in the 1976 International Solid-State Circuits Conference in Philadelphia. It was echoed repeatedly by memory-system designers and even by some memory manufacturers.
The occasion was the unveiling of the first 16,384-bit dynamic MOS RAM, an Intel development soon to reach the market (see
Edward A. Torrero Associate Editor

product feature in this issue, p. 101). But users and manufacturers alike were far from unanimous on Intel's claim that its approach was the right one. Dissent came especially on the matter of an output-data latch, the number of refresh cycles and the chip's power dissipation.
In a private meeting organized by J. Reese Brown, a Burroughs senior staff engineer, users and vendors clashed over the relative merits of Intel's new n-channel memory. Also contested were other approaches to be used by other memory makers, mos,t of whom plan a 16-k entry by year's end.
For memory users, the ominous

lack of agreement signified a new round of frustrations not unlike those that many feel sti ll envelop present 4096-bit dynamic MOS RAMs (see "4-k RAM Race Still Wide Open as Designers Try Different Paths," ED No. 6, Mar. 15, 1975, p. 26).
The 16-k bit RAM battle
At the heart of the 16-k-RAM debate is the extent fo which different manufacturers seek to duplicate some of the features of current 4-k RAMs housed in 16-pin DIPs.
This kind of package for 16-k RAMs is one of the few areas of

n'ii111r-..
A 16,384 x 1-bit n-channel MOS dynamic RAM employs single-transistor cells and two-layer polysilicon
26

!fl "iii! ~
technology. Intel's 2116 replaces the Chip Select of 16·pin 4·k RAMs with a seventh address pin.
ELECTRONIC DESIGN 7, March 29, 1976

NEW

SERIES 2850
DIGITAL PANEL METER
NOW... at the right price... a single DPM for popular
domestic and IEC/DIN cutouts
'
3 +1I C-' -. L_J

STANDARD CUTOUT 1.682" x 3.622"
(42.72 mm x 92 mm)

IEC/ DIN CUTOUT
1.77" x 3.622" (45 mm x 92 mm)

OTHER DOMESTIC CUTOUT l.682" x 3.92"
(42 .72 mm x 99.57 mm)

· 3Y2 digit readout · Automatic zero and polarity · 0.1 o/o of reading accuracy · BCD output is standard · Input/output edge connector included · Highly reliable LSI circuitry · Choice of 120/240 VAC, 50-400 Hz
or 5 voe operation
· OEM quantity prices available upon request.
ORDER FROM YOUR ELECTRONICS DISTRIBUTOR

Model 2850 120/240 VAe input; 0.55" planar gas discharge display complete with panel mounting clips, edge connector and manual. ..... .. . $138
o I 851 5 voe input, 0.55" planar gas dis-
charge display complete with panel mounting clips, edge connector and manual. . . . . . . . . 1 8
Model 2852 120/240 VAe input, 0.43" LED display complete with panel mounting clips, edge connector and manual. . . . . . . . . . . . . . . . . . . . . . $138
Model 2853 5 voe input, 0.43" LED display com-
plete with panel mounting clips, edge connector and manual. .... .. .. .. ............... .. . $138
STOCK DC CURRENT RANGES: 20 & 200 uA; 2, 20 & 200 mA STOCK DC VOLTAGE RANGES: 200 mV; 2, 20 & 200 V OTHER RANGES ON SPECIAL ORDER

KATY INDUSTRIES

SI PS ELEC RI COMPANY
853 Dundee Avenue, Elgin, Illinois 60120 · (312) 697-2260
CABLE : SIM ELCO · Telex: 72-2416 IN CANADA : Bach-Simpson, Ltd., London, Ontario IN ENGLAND: Bach-Simpson (U.K.) Ltd., Wadebridge, Cornwall IN INDIA: Ruttonsha-Simpson Private, Ltd., Vikhroli, Bombay

INDUSTRIAL EQUIPMENT
GROUP

CIRCLE NUMBER 12

DRAIN
------~
lf-L

VMOS transistors-vertical n-channel MOS devices formed on the face of a V-groove-form the basis of a developmental 16-k bit ROM from American Microsystems. The 5-V VMOS ROM has a worst-case access of 200 ns, compared with over 500 ns for equivalent ROMs that use conventional techniques.

agreement; it is used by Intel for its 16-k RAM, the 2116. However, companies like Nippon and Hitachi (which presented a late paper on its developmental 16-k RAM ) and possibly Texas Instruments (which didn't participate in the general discussions) are among those thought to be planning an 18 or 22-pin package.
The acknowledged model for the 16-pin package is Mostek's. The company pioneered the 16-pin package for 4-k RAMs. Sockets designed for that package can readily accommodate the similarly packaged, though hi gher-density, 16-k memory. This is done by abolishing Chip Select (CS) in favor of an extra address line (A6 ) supporting two address bits - as in Intel's 2116.
However, the 2116 also incorporates a special output latch like that found on early Mostek 4-k RAMs. That simple latch represents one of thP major points of dispute. Unlike a standard latch, the Mostek version maintains data in a V1alid state right into a succeeding memory cycle.
"For a chip designer," said Richard Foss, president of Mosaid in Canada, ",that latch violates one of the golden rules, that each cycle should be considered a separate entity. If in the next cycle, you have to worry about what happened in the last cycle, you can't restandardize. It's a no-no for testing."
Moreover, the use of Chip Select was one way to clear the output latch in the 4-k RAM. But Chip

Select isn't available on 16-k RAMs going into 16-pin packages. Device selection is now an additional function of either the column-address strobe (CAS) signal, which determines the vertical cells to be accessed, or the row-address strobe (RAS), which pinpoints horizontal cells.
Refresh woes
The absence of Chip Select can be a particularly acute problem for existing 4-k-RAM-based systems that refresh the dynamic memories with hidden, or "transparent," techniques. The techniques make use of the fact that not a ll memory elements are accessed at the same time, and ·are ideal for large memory systems, such as t hose employed by Honeywell.
While some of the elements are activated by row and column-address signals, other elements have t heir column-add1·ess signals cut off, and are refreshed by RAS. The so-call ed RA S-only r efresh isn't possible with a memory chip that contains the output latch.
"With a data-out latch, you have to provide CAS to all chips whether you want to or not in order to turn off the data-out from a previously accessed chip," said Paul Schroeder, Mostek's senior design engineer in charge of 16-k RAM development.
"All of the things you need to do to get around this are extremely unpleasant. They're not the kind of things a system designer really wants to do."

For Intel, a strong argument for the latch is that it exist s on current 4-k RAMS. Company spokesmen make much of the fact that they can replace the 4-ks in a customer's board with 16-k-RAM samples. The board then works just as if the memories had not been replaced.
Although the 16-k RAMs function as 4-ks- only one quadrant is used-the customer can perform most of his testing. He can check pattern sensitivities, access times and power dissipation. And with an extra address line, he can multiply storage capacity by four.
"I think the customer has been rlone a disservice by this debate," said David House, I ntel's component applications manager. The decision of some manufacturers to rlrop the latch on their 16-ks, according to House, was a poor business decision, rather than an obvious engineering decision.
"It's definitely not clear that the output latch should not be there."
For -t he great bulk of applications, an output latch on the 16-k RAM presents no problem, observes House. In fact most memory systems can be readily designed to accommodate both a memory chi p wi1th the latch and a memory chip without one.
Such a system must be able to sample data when the clocks are in a Valid state, so t hat the latchless part works, and mu st not depend on the owtput being in a high-impedance state- so that the memory with the latch, like Intel's 2116,

28

CIRCLE NUMBER 13 ....

can also work. Most manufacturers declined to
detail how they would design their 16-k RAM chip, although American Microsystems indicated it would follow Intel's lead in building a 16-k version of Mostek's early 4-k RAM.
Mostek, however, was adamant in its opposition to the kind of latch it originally inflicted on the industry. The Mostek 16-k RAM, which could be announced as early as midyear, will have a data latch, but one that can be cleared at the end of a memory cycle, when CAS goes high.
The benefits are many. Now
a CAS signal can be used as a separate Chip Select and to simplify the expansion of speed-enhancing page-mode systems. Multiple 16-ks are accessed with a RAS pulse, and a CAS is applied only to those chips from which ourtputs are needed. Further, the memory chip can be used in systems that call for transparent refresh.
Another point of controversy is the number of refresh cycles. If compatibility with 4-k RAMs were the sole consideration, the number of refresh cycles would be 64 every 2 ms.
The Intel 16-k RAM allows either 64 or 128 cycles in the 2-ms refresh interval. The memory naturally takes 128 cycles, because of its 128

x 128-element layout. However, internal logic can reduce the refresh requirement to 64 when signalled to do so by a special overlapping of CAS and RAS.
For system designers, 64 cycles would seem .to be better than 128. The reduced refresh requirement leads to a somewhat simpler design and to lessened "dead" time.
Critics argue, though, that with a 64-cycle refresh, twice as many sense ·amps are active than there would be with 128 cycles. The additional amps increase power dissipation.
"Chip rtemperature could rise by 10 C," said Foss. "If it does, never mind the data sheets, you may have to refresh twice as often, because the chip is that much hotter."
Further, the 2116 has a total of 64 cells on each sense amp, and a total of 256 space-consuming sense
amps on the 145 x 235-mil die-
close to the maximum size that will sit in a 16-pin DIP, "without using a shoehorn," as one expert put it.
When the refresh requirement is solely 128 cycles, a smaller chip can be built with just 128 cells on each sense amp and a 1total of 128 sense amps-the approach planned by Mostek.
The result, according to Mostek's Schroeder, will be a chip measuring about 28,000 square mils, com-

pared with 34,000 for the 2116. And the Mostek version will spec its slowest access at 250 nswhich is the top speed for the 2116.
"I expect ·the highest speed to be 200 ns early in the game," Schroeder said, "and faster units will appear later."
Dissipati ng power
The 2116's power dissipation was another point of concern. Although the memory was said to· consume substantially less power/bit than a 4-k RAM did, the 2116's over-all dissipation was abouit the sameofficially under 3/4 W. For some, the value was too high.
"The arithmetic I've gone through," Schroeder said, "makes me expect that parts having dissipations over 1/2 W tend to have a high junction temperature. If it rises by no more than 10 C, I wou ld be surprised."
That rise could spell trouble for the refresh interval. Published specs don't always take into account the rise in junction temperature. One way to make the spec more meaningful, according to Schroeder, is for manufacturers to test refresh interval with internal junction temperatures at 100 C or higher, and to provide curves of ambient temperature and air flow as functions of cycle rate. ··

Lack of standards slows progress of analog interfacing for µP systems

Despite impressive advances in the design of monolithic analogto-digital converters, widespread use of microprocessors in analog systems may be stymied, an expert warned, unless the industry acts immediately to standardize converter hardware.
The call for action came from Hermann Schmid, a consultant for General Electric. Schmid summed up the problem during a panel discussion on "Problems of Analog Interface in Microprocessor-Based
Michael Elphick Managing Editor
30

Systems" at the ISSCC. "There must be hundreds of a/ d
and d/ a converters on the market," he said, "but have you ever tried to find a second source for one of them?"
Few circuits are pin-compatible, Schmid added, and they come in all sorts of shapes and sizes and with various voltage requirements. And when you try to interface them with µ,Ps you run into still further problems.
To be useful, the analog interface device should be address selectable, have on-board latches, and

have three-state digital outputs for direct connection to the µ,P's bus, Schmid said.
"Standardization is difficult and we shouldn't underestimate the magnitude of the task," warned Schmid. "But, it must be done. The IEEE interface-bus standard for instruments is an excellent example of what is possible."
Most panelists agreed there was an urgent need for standards. Tom Harper of National Semiconductor said system designers he's worked with seem to be using µ,Ps primarily to reduce their parts count.
ELECTRONIC DESIGN 7, March 29, 1976

SC/MR·· A MICROPROCESSOR SO SIMPLE AND INEXPENSIVE, IT'S ENOUGH
TO MAKE.ANY MACHINE THINK.

The"Simple Cheap Microprocessor:'

It requires a minimum number of

At less than ten bucks apiece in

components and support chips.

volume, it makes microprocessor tech-

Yet it gives you advantages that can't

nology practical where it's never made be found in many expensive micropro-

sense before. In products like meters; cessors. Like anon-chip clock. Serial I/O

ports that are TTL-

compatible. Static

operation. Bus allo-

cation for multi-

processor system

design. Plus built-in,

programmable

DELAY instruction.

It's on your

distributor's shelf

right now. For tech-

nical description

of the chip and a com-

plete data sheet, send

us the coupon below.

gas pumps, traffic-light controls, pinball

Ifthis thing catches on (and at less

machines, medical electronics, TV games, than $10 a copy, it's got to), who knows

scales, motor controls, telephones, home where it could lead?

appliances.

To stuffed dogs that tell shaggy

A whole world of machines and men people-stories?

has been waiting for such a thing. Well, thanks to National, SC/MP is
here now. And it's not just the cheapest, least-
complicated microprocessor on the market. It's also one of the most capable.
It shortens design time because of its architecture, and its ability to interface with standard memories and standard peripheral components.

r-----------

I I

National Semiconductor Corporation 2900 Semiconductor Drive Santa Ciara, California 95051

-

-

-

-

-

-

-

, I
I

I I

Ge ntlemen : SC/ MP, eh? I'd like to see thatTechnical Description, data

I I

I sheet and a sales brochure:

I

I Name

Title

I

I Company

I

I Address

I

I City

Stat

Zip_ _ I

L---~--------------~

National Semiconductor~

Ask your distributor for our SC/MP Evaluation Kit.

EL ECTRONIC D ESIGN 7, March 29, 1976

31

When substantial hardware is needed for analog interfacing it defeats the purpose of using a 11-P:
Microprocessor manufacturers may start to include -analoginterface circuitry on the µP chips, and system designers may start -to replace external hardware with software algorithms, he warned, unless converter manufacturers act quickly to s upply compact standardized hardware at low cost.
"Converter manufacturers aren't merely competing with each other," explained Harper. "The real competition is software."
Panelists also agreed that the standardizati on task would be Herculean. Since it would be practically impossible to standardize the software aspects of analog interfacing without standards for the µP s themselves, Schmid urged the industry to begin with hardware standardization and resolve software problems later.
Even m the hardware area, though, prospects for standardization appeared bleak. While most panelists agreed on the need for addressing capability and threestate TTL digital signals, the panel was sharply divided on the basic question of whether digital data should be handled serially or in parallel.
The hardware's getting better
Although standardization remains elusive, papers presented at the conference showed that IC manufacturers have licked several other problems that tended to restrict use of µPs in analog systems. A/ d and d/ a convertei:s no longer need to be expensive, slow, inaccurate and bulky.
IC designers proved at this year's conference that most of the traditional constraints have been overcome. It's now possible to build single-chip a / d converters using just about any popular circuit configuration.
Among the developmental a/ d converters described at the conference were circuits using CMOS, PMOS and bipolar-LSI processing. Circuit techniques used included dual-slope integration, successive approximation and hi gh-speed parallel conversion.
Perhaps the most impressive a/d converter described at the confer-

START CONVERSION

ON-CHIP 5 V

BILATERAL

VOLTAGE

REFERENCE

C4

ON-CHI P CLOCK

AUTO-ZERO CAPACITORS
Dual-slope integration is the conversion technique used in a monolithic CMOS
a a/d converter designed by RCA. The 11-bit circuit includes a clock oscillator
and a reference source. It operates from single-ended supply of 4.5 to 15 V.

ence was a successive-approximation circuit, from TRW Systems, that combines speed with accuracy. The 10-bit bipolar-LSI circuit achieves a sampling rate of 5 MHz while consuming only 2.7 W.
Linearity of the basic circuit is 0.4 LSB, but can be improved to less than 0.2 LSB by laser trimming of the chip's thin-film resistors. The only external circuitry needed is a reference source and a clock oscillator. ( For a block diagram and more complete description of this circuit, see "Fastest Monolithic 10-bit A/ d Device Has 200-ns Conversion Time," ED 5, March 1, 1976, p. 20. )
Although the Systems Group of TRW traditionally doesn't sell components, the company may market the converter circuit later in the year, according to David Breuer. who presented the paper.
Even higher conversion speeds are achieved in a bipolar a / d converter described by Robert Nordstrom of Tektronix. This circuit · uses a parallel-conversion technique to achieve a conversion rate of 100 MHz, and the 4-bit chip has sufficient accuracy for use in an 8-bit converter.
The circuit consists essentially of 16 high-speed comparators and a 4-bit binary encoder, integrated on a single chip. A separate resistor network was used for the prototype, which was built primarily to demonstrate the feasibility of inte-

grating the comparators . Other manufacturers have dem-
onstrated that it's possible to deposit and trim thin-film resistors on a silicon chip, so it should be possible to build a complete monolithic converter based on thi s design. Each compa rator cell consists of only 15 transistors, and standard high-frequency IC processing is used to achieve an fT of 3 GHz for the transistors. The bit lines deliver ECL levels, but diss ipation is on ly 32 mW for each comparator cell.
MOS shows progress, too
Bipolar circu its won the speed race at ISSCC, but some solid gains were also made in MOS. Of course, for a/ d converters, MOS offers the advantages of low cost, high circuit density and low power dissipation. But until recently designers found it difficult to achieve the required performance in the analog portion of a / d converters that employed MOS throughout.
Most designers compromised on a two-chip arrangement, using MOS for the digital portion and bipolar circuitry for the analog section. Now, however, the analog design problems seem to be licked. Three companies announced s inglechip MOS converter s at the conference--two use CMOS, while one uses PMOS.
One of the CMOS circuits was

32

ELECTRON IC DESIGN 7, March 29, 1976

''No,we ordered

,, O.K., friends, here it is, our DAC-03 monolithic 0/A converter. 10-bits, 10 bucks. Lowest cost unit you can find

that contains all necessary functions:

a ten-buck DACI

precision voltage reference, current sources, current steering logic, R-2R resistor ladder network, and a high speed internally compensated op amp.

You save dollars, pounds and p.c.

board real estate. And you get

guaranteed key specs at no extra

charge.

Add it all up-price, performance,

and PMI's history of delivering more

monolithic DACs than all other

manufacturers combined. Then ask

for data sheets on our DAC line.

You won't have to look anywhere

else for the DAC you need; the buck

stops here.

PredOO1n50M0oSnpoalcletPhair~k,DIrniv<e.,,, I PMI~

Santa Clara, CA 95050

(4081 246-9222. TWX 910-

®

338-0528. Ca bl e MONO .

CIRCLE NUMBER 15

described by Robert Huntington of Motorola Semiconductor Products. His 3-1/ 2-digit a / d converter provides autopolarity and automaticzero functions.
Also, it compensates itself for opamp offsets and the comparator threshold. As a result, the modified dual-slope circuit holds its 0.05 % full-scale accuracy over a
temperature range of - 50 to + 75
C and eliminates the need for manual adjustments.
The single-chip circuit needs no precision off-chip components, but does require a couple of noncritical capacitors and a resistor. Powersupply requirements are ± 5 V at less than 2 mA.
A second CMOS a/ d converter was described by Andrew Dingwall of RCA's Solid State Technology Center. The circuit is an 11-bit autostabilized single-chip design that operates from a single 4.5-to15-V unregulated power supply with a current drain of only 1.2 mA at 5 V.
Like the Motorola circuit, the the RCA version uses a modified dual-slope conversion technique. Single-supply operation was achieved by use of a current-mirror

REFERENCE VOLTAGE
D/ A
CONVERTER

START

8-BIT OUTPUT

Successive approximation provides a typical conversion time of 20 µs in an 8-bit PMOS monolithic a/d converter from National Semiconductor. Use of an external reference allows ratiometric operation. The complete circuit has been fabricated on a single 120 x 123-mil chip using p-channel, metal -gate , processing.

configuration in the amplifier portion of the CMOS circuit. The reference voltage can be externally suppli ed or derived from an optional on-chip zener diode--in which case the operating-temperature ·range is reduced. The clock oscillator is included on the chip, but some noncritical, external passive components are needed.
A third MOS a / d converter,

using p-channel, metal-gate processing, was described by Adib Hamade. He now wo1'k3 in Iraq, but designed the single-chip 8-bit conn·rte1· whi le working for National Semiconductor in the l'.S.
The circuit employs a success1veapproximation conversion tec.:hnique to yield a typical conversion time of 20 µs. The 120 x 123-mil PMOS chip includes a d/ a converter, a comparator, control logic and three-state output buffers. Because MOS is used for the comparator, the analog input impedance is greater than 1000 Mn. The reference voltage is provided externally, thus allowing ratiometric operation.
According to Hamade, the unit exhibits 1/ 4-bit step linearity with acceptable production yield, and linearity degrades only slightly over the temperature range from
- 55 to + 125 C. The designer pre-
dicts that it should be possible to build a monolithic 10-bit converter using the same circuit techniques.
Diffused resistors are used in the inherently low-cost design, and, in a clever layout trick, small protrusions from the resistor di ...,usion act as sources for PMOS switching transistors. · ·

CCDs reach practical stage for analog signal processing

Applying charge-coupled devit:l's (CCDs) to analog-signal processing has finally begun to achieve prac.:tical results. A variety of useroriented hardware was described at last month's ISSCC.
The application concept--introduced a scant two years ago-has begun to emerge from university and industrial laboratories in such forms as video delay lines, analog transversal filters, signal correlators, and lenses for ultrasonic imaging systems.
CCD signal-processing devices offer great potential for lowered cost and reduced complexity over present-day signal-processing equipment. A host of new markets (plus increased competition in
Samuel Derman
Associate Editor

some existing ones ) was predicted once these cost goals have been realized.
These devices have passed well beyond the feasibility stage, experts emphasized. As evidence, working specifications for CCD based hardware were given for such characteristics as linearity, distortion, dynamic range and bandwidth.
"What the engineer wants to know now is whether · it's good enough for his application," said Carlo Sequin of Bell Labs, Murray Hill, J.
"Engineers don't just think·of a CCD as an isolated device. They want a working black box that can perform a particular function."
David Wen of Fairchild, Palo Alto, CA, introduced one of several of these CCD-implemented units, a video-delay line.

The Fairchild delay line serves a:
number of important needs of the video industry, Wen explained.
One use is for television timebase correction, which is needed when the TV signal is obtained from a video tape or disc_ Any existing irregularities in the mechanism that drives the disc or tape reels results in timing-synchronization errors. The CCD dela~- line can correct the errors by sampling the signal at one frequency and retransmitting it at another, thus changing the effective timing.
Currently, such correction is accompli shed by digital techniques that require a/d and d/ a converters to transfer the signal into and out of the digital domain. All this very elaborate hardware can be replaced by just one CCD, Wen pointed out.
Another application for the CCD

34

ELECTRONIC DESIGN 7, March 29, 1976

CIRCLE NUMBER 16

Good news from Hughes:

Now you can
actually reduce system cost by using our hybrid m1· croc1· rcu1· t modules.

If you're designing circuits that

have to be both cost-effective and high

in reliability, it will probably pay you to

talk with us.

We 've developed a system for

condensing circuit requirements into

the most efficient hybrid packages

possible. And we can help you reduce

size and weight as well as

manufacturing costs.

·

Here's how we do it: We design

the hybrid circuits, develop

the prototypes, manu-

'l/.

facture custom com-

//,.

ponents, then

% '/ assemble, test,

/%%, and guarantee the

I// total hybrid package.

/

We make both

thick film and

thin film hy-

brids . We use

hermetically-

sealed metal

and ceramic

packages. And we

make custom MOS

devices and bipolar

chips right here in-

house.

We produce hybrid modules

lume quantities at competitive

s, as well as small quantities for

product development.

Result: Now you can work with the

one company best equipped and experi-

enced to handle your job from concept

through production .

We must be doing a lot of things

right, because we're one of the leading

producers of custom hybrid circuits.

So when it comes to hybrids, call

on Hughes . Especially if quality is as

important as price. Write for additional

information: 500 Superior Avenue,

- Newport Beach , CA 92663 , Att 'n.
Hybrid Dept. Or call (714) 548-0671 , ext. 204.

r------------------,

I

I

i HUGHES i

I

I

LH-UG--H-ES--A-IR-C-R-A-FT--C-O-M-P-A-N~Y

M IC ROELECTRONIC PRODUCTS DIVISION

delay line is in separating color from black and white in a composite TV signal.
The Fairchild CCD delay line consists of two independent 455element buried-channel CCD shift registers, complete with transport clocks and input and output termi-
nals, all on a die measuring 79 x
84 mils. The unit has a bandwidth of 4 to 5 MHz, a dynamic range of about 55 dB and nonlinearity of 3 percent or less. Only two external clocks are required.
The output signal of one register can be directly connected to the input terminal of the other to obtain a 910-element delay capable of storing a complete horizontal line of standard television transmission (63.55 µs ) with a sampling rate of 14.32 MHz. The device is assembled into a standard 16-lead DIP .
The delay line will become available "very soon," Wen reported. The price for single units will initially be somewhere in the $100 to $200 range, with the projected price eventually dropping to less than five dollars each for quantity lots. The current price of an equivalent standard delay line is $700 to $800.
CCDs filter baseband data
An analog CCD transversal filter for baseband data filtering was described by MarYin White, advisory engineer at Westinghouse Advanced Technology Laboratories, Baltimore. :VT D.
A CCD transversal filter consists basically of a tapped CCD delay line. At each tap the signal

leaves the delay line and passes through a separate variable resistance. Finally, the delayed signals, from each tap, are summed.
Since each resistance can be varied independently, the result is a summation of weighted signals. Any desired filter ·characteristic can be synthesized by this means. This is a powerful design tool, White explained, because it allows the designer to control a filter's amplitude and phase characteristics independentty. In conventional passive filters the amplitude and phase are unavoidably related.
Even more important, said White, the individual resistances can be varied electrically, and the weighting factors can be continuously upgraded in accordance with some specified algorithm. This process, known as adaptive filtering, oITers the possibility of enormous improvement in signal-to-noise ratio in such diverse areas as radar reception, echo suppression in satellite communications, and biomedical electronics. For example, it can remove 60 Hz noise from electrocardiogram signals, or separate the heartbeats of fetus and mother.
White provided the following figures for the filter: total harmonic distortion of 0.3 percent for a 1.5-V p-p 1-kHz input signal and a sampling frequency of 16.7 kHz.
White explained that a unique design feature of this device is the use of a floating-dock electrode sensor that provides nondestructive readout (at each tap point) of the CCD delay-line signal. The unit combines both bipolar and MOS technology with the CCD delay line

- the first time such a combination has been realized on a single chip.
Completion of the entire system must await the integration of the adaptive-filter algorithm on the chip, White said.
CCDs convolute analog inputs
Patrick Bosshart, an electricalengineering graduate student at MIT, described an integrated-circuit analog correlator that uses CCDs. An analog correlator performs the convolution of two arbitrary analog input functions and can replace some complex digita1 systems that do the same job. The CCD correlator, however, uses fewer components and costs Jess to manufacture.
The device, based on a master's thesis project, was designed by Bosshart and fabricated at Texas Instruments.
The level of performance is high enough to allow the correlator to be used in applications in audio and video-signal processing and in adaptive filtering Bosshart reported.
Potential improvements in ultrasound technology for both medical and industrial applications using a cascade CCD were described by John Short of Stanford University, Stanford, CA.
This device uses CCD delay lines to equalize the total (electronic plus acoustic) propagation time for a set of ultrasonic transducers.
The CCD "lens" has been built and tested and has been shown to produce a resolution near the theoretical maximum for an array of 1.5-MHz transducers. · ·

Telephone-oriented LSI finds tough going despite reported advances

The role of standard IC products-and particularly microprocessors- in the multi-billion-dollar telephone industry appears cloudy.
Despite LSI-circuit innovations described at the 1976 ISSCC, a panel discussion on the future impact of such circuits brought
Stanley Runyon Associate Editor
)6

out controversies surrounding new semiconductor developments. It also underscored the long, rocky road ICs must travel before finding acceptance in telephone equipment.
Papers described at the conference covered three major areas in telephony: coder/ decoders (codecs), compressor I expand ors (compandors) and crosspoint switches.

One switch unveiled at the meeting is notable for havi ::g its control circuits, which can interface directly with a microprocessor, integrated on the same chip as the crosspoint array.
Microprocessor control may indeed be an attractive feature. But the question is, can the microprocessor, or an y of the other communications circuits described at
ELECTRONIC DESIGN 7, March 29, 1976

the conference, find a prominent niche in an industry famous for its caution. If some of the panelists and audience at the informal discussion have their way, the answer is "no."
Although John C. McDonald, vice president of research and engineering for the Vidar Div. of TRW, Mountain View, CA, projected a $3 billion market for LSI/ MSI circuits in telephone networks by 1990, others took a different view:
John Rhodes, organizer and moderator of the session, and a technical member of the board of PyeTMC, a supplier of phone equipment in Wilts, England, stated

MOWA FAIL-SAFE
SOLID·STJJE RELAY
Most sol id-state relays have a nasty tendency to stick in the "on" condition if a voltage or current surge hits them. And, if the triac fails to fire, many even burn up and become the unfortunate cause of catastrophic system failures.
Not ours. A unique combination of dv/dt snubber, fusible-link protection, and an overdesigned triac makes the new optically-coupled Heinemann SSRs fail-safe. Now, the worst thing that can happen to your system is the simple need to replace the relay. That's a lot better than having to reprogram your entire control sequence, isn't it? We make our new SSRs for either zero-voltage or non-zerovoltage switching, and both types are rated for maximum ac load currents of 5A or 10A Any control voltage from 3Vdc to 32Vdc; all models compatible with TIL, DTL, and CMOS logic. And you have a choice of solder-pin, quick-on, and screw terminals. Talk with Bob Kusek (609-882-4800) or write for further informa- ·
EMAN N tion.Heinemann Electric Company, HE~N
I Brunswick Pike,Trenton, NJ08602.
We keep you out of trouble.

An 88 x 92-mil analog compandor uses ion imp la ntation a nd matched components to achieve low drift, high accuracy.
flatly that "processing and microprocessors are not for telephony." Rhodes apparently meant off-theshelf silicon products, not custom LSI, of which he proclaimed himself a proponent. Asked to define "custom LSI" Rhodes replied: "It's an IC designed by an engineer who knows the telephone business."
Winners and losers
McDonald, on the other hand, told of considerable success with standard ICs, and of disasters with custom circuits. His formula for success: 100 to 500 FITs ( failures in 109 hours ) , availability for 20 years or more, and, of course, low price.
Attendees and panelists immediately polarized, lining up on either the custom or standardproduct side. While this appeared
ELECTRONIC DESIGN 7, March 29, 1976

CIRCLE NUMBER 17
37

SAVE WEAR AND TEAR ON YOUR CIRCUITS,
YOUR NERVES AND YOUR BUDGET.
Proto-ClipTM: Foolproof, short-proof, power-on DIP in-circuit testing.

Wherever you use DI P's, you need CSC Proto-Cl ips.**The clipon, short-proof way to bri ng leads up from crowded circuit boards, for fast signaltracing , testing, signal injection ... even wiring unused circuits into existing boards. Unique gripping teeth (see inset) provide slip-proof connections for test-equipment probes . .. free your hands for other work. High-i mpact plastic construction eliminates troublesome springs and pivots; molded
Ullll

flexible web insures positivt operation for thousands of tests ; non-corrod ing nickelsilver contacts give simultaneous, low-resistance connections to all IC leads.
Proto-Clips are available with or without cable for 14-, 16- and 24-pin DIP's.
Best of all , Proto- . Clips are inexpensive!
For more information, write for our full product catalog and distri butor list. ~
~~~1i1111iu11

PC-14 (14-pin Proto-Clip) $4.50 each ~

PC-16 (16-pin Proto-Clip) $4.75 each ~

NEW! PC-24 (24-pin Proto-Clip)
$8.50 each ~

© 1975 Continental Specialties Corp. 38

*Manufacturer's recommended retail
··u.s. Pat. No. 3.914.007
CI RCLE NUMBER 18

to be the key issue of the session, the debate actually surfaced as a clash between two giant but antithetical industries- the slow moving telephone establishment and the quick-turnover semiconductor houses.
Just how quickly semiconductor technology can respond to a specific job is demonsitrated by the advances outlined at the conference.
In a paper on an all-MOS, companded PCM voice encoder, John P. Tsividis of the University of California, Berkeley, CA, described a partially integrated MOS chip that meets Bell System specifications for signal-to-distortion ratio, gain tracking, single-frequency distortion and idle-channel noise.
Tsividis explained that the chip, fabricated as metal-gate, n-channel MOS, satisfies a commonly used companding algorithm (µ,-255 ) that uses a 15-segment approximation of the nonlinear curve. Thus the sin ratio is op,timized for digital voice transmission.
Analog is king in telephony
Most existing telephone equipment, however, still operates in the analog domain. To improve the s/n ·ratio of analog transmission, companding remains the traditional technique. Here, a 2-dB change in input level is compressed into a 1-dB variation for transmission, and an expandor restores the 2-dB excursion at the receiving end .
A monolithic compandor was described by Craig Todd of Signetics. As he pointed out, discrete compandors require many components, and so o{ten suffer from excessive temperature drift. The bipolar IC, however, uses ion-implanted resistors and matched IC components, so that the required low-level tracking, distortion and temperature stability are realized without costly external trimming.
The untrimmed distortion of the IC compandor, Todd stated, is 0.5 percent, and the gain change from - 40 to 70 C is only ±0.2 dB. An01ther benefit : low power consumption-j ust 4 mA are drawn at a V ee ranging from 6 to 18 V.
In the third important application area-that of switching-two ICs that were described met the challenge of low distortion, low loss and low crosstalk. Though
ELECTRONIC DESIGN 7, March 29, 1976

electromechanical relays aptly fulfill these requirements, soli d-state crosspoints are potentially more reliable, switch much faster than relays and need far less power.
The first I C-outlined by Willy Sansen of Catholic University, Heverlee, Belgium, is an active,
bipolar 4 x 4 crosspoint with a
low r ou-area product ( 1.7 to 2.5 n -mm"), with low sensitivity to line spikes, and needing no couplin g transformers or capacitors.
In operaition, the pass transistor of the switch is biased in its active region-instead of the linear region-and the device gain is arranged in a feedback loop to reduce the ON resistance and cut losses. Insertion loss of the switch is as low as 0.1 dB, and ON dissipation is fairly high-80 mW-compared with that of other solid-state methods.
Switching plus digital control
In another approach, Thomas Cauge of Signetics told of a DMOS crosspoint array in which control circuitry was integrated on the same chip. Configured as
an 8 x 2 unbalanced network, the
switch ON resistance is ·Cut by a facto·r o.f three to· five over that of conventio·nal MOS that uses the same area.
Cauge listed both the typical crosstalk and OFF isolation of the DMOS switch as -105 dB, and
typical ON resistance as 12 n at
a Vc-c of 15 V. He noted that the TTL/CMOS compatibility of the chip and the single 15-V supply needed are features designed expressly for mic;roprocessor interfacing. ··
Papers, anyone?
A complete digest of the papers presented at the International Solid-State Circuits Conference is avai lable at $20 for IEEE members and $30 for nonmembers. Write to: International Solid-State Circuits Conference, Philadelphia Section IEEE Office, Moore School of Electrical Engineeri ng, University of Pennsylvania, Philadelphia, PA 19174.

We can deli

rld's smallest

1800 air varia capacitors.

On time.
And since we're nice people, we don 't even charge much for them. So if you have an application that calls for-a sub-miniature capacitor that you can "tweak" to a specific frequency, these Johnson trimmers are ideal.
You can choose from either PC or stripline mount, either vertical or horizontal tuning. These Type "T" capacitors are about one-third the size of thefamiliartype " U" capacitors. so you can save space, cut costs and insure improved performance in the most compact electronic equipment.
Rotors and stators are precision-machined from solid brass extrusions, resulting in exceptional stability and uniformity. High Q-typically 2000at150 MHz. Temperature coefficient is a low plus 30 ± 15 ppm/ °C. High torque (1Y2 to8 oz./ inches) holds rotor securely under vibration.They're designed to meet or exceed EIA-RS 204 and MIL Standard 202C Methods 204A and 201 A
In short, these capacitors may be just what you 've been looking for. It'll only cost you a stamp to get more information. And if you give us your phone number, we'll call you and send free samples after we have clarified your application .
---E-.F.-JO-HN-S-ON-C-OM-P-AN-Y ------------3305Tenth Ave . SW. /Waseca, MN . 56093
D Please send me technical informati.on on the type T.
D Also , include information on your entire line of variable capacitors.
DI want test samples. Please call me at _ _ _ _ _ __
TNITA LEM_E_-_ -- _-_-_-_-_ -_ -_ -_ -_ -_ -_ -_ -_ -_ -_~
FIRM _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __

ADDRESS CITY_ _ _ _ _ _ _ STATE

ZIP_ _

E. f. JOHNSON l:OMPANY

ELECTRON IC DESIGN 7. March 29, 1976

CIRCLE NUMBER 19 39

YlllEEI CIRlllFlll
RESISTORS RIM

Carbon comp resistors, lik a lot of

m foods, have tie

popped into the oven b(jfore they're ready for use. But right there,

the similarity ends. Because while "brown 'n serv " ype t ds

mean convenience, there's certainly nothing convenient about bak-

ing resistors so they'll perform in a circuit with halfway decent

stability.

Let's get serious. If you really want stability-built-in, all-

climate stability-switch over to the high performance, low cost

carbon film resistors from Mepco/Electra. Here's why: Under hu-

midity testing, carbon film resistors, will change a maximum of 3%

while carbon comps will change anywhere from 5 to 15%. Your

circuit operates more reliably with carbon film resistors, and you

need no designed-in compensations for future climatic changes.

The temperature coefficient of carbon film resistors is -300

±70 PPM/0c while carbon comps can be anywhere between +1000

and -500 PPM/0c. Carbon films give you a more precise circuit

Columbia Road. Morristown. N.J. 07960

(20!) 539-2000

CIRCLE NUMBER 20

ELECT RONIC D ES IGN 7, March 29, 1976

OUR CUP RUNNETHO
Thanks. Since we offered our UGLY MUG~we've been flooded with quotation requests and we love it. If you 're one of the engineers that got one of our quotes,you probably love it too. Because we're the company that makes the modular de supplies that solve 90% of your computer peripheral and instrumentation problems for as little as 53¢/watt. 16 voltages up to 28V and currents to 100A; ±0.1% regulation , ripple-and-noise ; remote sensing ; spike suppression ; foldback current limiting; and 120/ 240V inputs. All standard features , not high-cost options . And we've got a complete custom capability that can give you 4, 5 or more outputs, with increased currents and higher voltages. Provide power sequencing and failure detection. Or even build you a complete UPS. And none of it costs much more-or takes much longer-than our standard supplies. If you missed all this the first time aroun.d , you 've still got a second chance: just send us an RFQ with " UGLY LIVES " scrawled , scribbled or typed across it and we 'll get back to you with a quote and a free UGLY MUG . But do it now-this has got to be the best offer you 've seen all day.
~'~!!~ve~~!!!t7!Y~~!-!!1 ~§
CIRCLE NUMBER 21
<Cl Elpac Electronics, Inc.

for your

HIGH

offers

VOLTAGE KEPCO a choice:

NEEDS

OPS
grouplXB

A P H i;;::::===I AUTOMATIC CROSSOVER

High Speed (no output capacitor) operational power amplifier-type
instruments for your control requirements
OPS 5008: 0-500V @ 40 mA OPS 10008: 0-1000V @20 mA OPS 20008: 0-2000V@ 10 mA

Conventionally filtered (low noise) bench style voltage and current stabilizers for your stable high voltage requirements
APH 5008: 0-500V @ 40 mA APH 10008: 0-1 OOOV @20 mA APH 20008: 0-2000V@ 10 mA

You may exercise control over the high voltage output with a 0-5V control signal, or use the built-in pre-amplifier to scale or sum your inputs operationally. The output follows input signals with a 100µsec programming time constant (OPS 5008) . Current limit is both adjustable and electrically programmable.
Slew Rate Limit . . . . . . . . . . . . . . 1 V /µsec. Gain . . . . . . . . . . . . . . . . . . . . . 106 VIV Offset Voltage (for Load) ......... <10 µV Noise . . . . . . . . . 0.01% of E0 or 15 mV rms

Control voltage with a 10-turn precision panel control (or program like the OPS) . Another 10-turn panel control adjusts the output current. LED annunciators signal operation in either voltage mode or current modes. A built-in "uncommitted preamplifier" is available for scaling or summing programming inputs. Output is monitored on a pair of 2%" meters.
Stabilization (for Load) . . . . ..... <0.005% 8-hour Drift ................. <0.01% Noise .. . . . . . . . . . . . . . . . . . <1 mV rms

Write Dept. FG - 05

Kepco high voltage power supplies are designed with your needs in mind. Our Catalog describes models ranging up to 5000 volts; up to 200 watts and includes both unipolar and bipolar instruments.
with KEPCO you're in controlI

KEPCO, INC.· 131 -38 SANFORD AVENUE· FLUSHING . NY 11352 US.A · 1212) 461-7000 ·TWX =710-582-2631 ·Cable: KEPCOPOWER NEWYORK
CIRCLE NUMBER 22

42

ELLCTRO ' IC DESIGN 7. March 29, 1976

1. ~
Wasltiitgton Report

NASA to develop hand-carried satellite ground terminals
The National Aeronautics and Space Administration is developing a technology base to support a new family of communication satellites for the 1980s. Trends indicate that both fixed and mobile terminals will be smaller and cheaper, and that many will be hand-carried.
The new services would aid in search and rescue and in disaster warning, would collect environmental data from thousands of floating or fixed unattended platforms throughout the world and would offer such capabilities as two-way video and voice transmissions.
NASA will continue research in high-power transmitters and in sensitive receivers. Another component of interest is an antenna that has commandable, adaptive beam contouring for confining transmissions to selected geographic areas.
Because of ·the growing demand for frequency allocations and the steadily aggravated spectrum crowding on lower frequencies, NASA will maintain current efforts to alleviate overcrowding, while also pursuing a long-range interest in opening up higher frequencies in the spectrum, which are still unused.

Lasers gain status in energy program
The Energy Research and Development Administration has realigned its laser and electron-beam fusion programs and its laser-isotope separation program in recognition of the increasing importance of laser~ in the energy field.
Both were formerly under ERDA's Division of Military Applications. Now laser and electron-beam fusion prog~·ams will come under a newly created Division of Laser Fusion. Laser isotope separation programs move over to the Division of Nuclear Research and Application as part of ERDA's long-range plan for nuclear fuel enrichment.
ERDA has received proposals for four enrichment projects from private industry, both for building the conventional gaseous-diffusion plants, and for building plants that would use the newer centrifuge approach. But the agency has announced interest in an enrichment approach-laser isotope separation-that might have an even lower cost. Its goal is construction of a laser-enrichment plant by late 1980s.

Patent system may be overhauled
Inventors shouldn't get their hopes up too soon, but reform of the nation's patent system is on the way. Patents in the future may cost less to gain, less to maintain, be less susceptible to challenge because they'll

ELECTRONIC D ESIGN 7. March 29, 1976

43

be better validated, and have a better image around the world. These are some of the heralded benefits of S. 2255, "The Patent Act
of 1975," which sailed through the Senate so quickly on Feb. 26 that opponents were caught flatfooted. The bill was passed by ·a voice vote, without any debate, and sent to the House. Angry protests are expected from such groups as the organized patent bar and the furor will likely produce intensive hearings in the House.
Basically, the reform measure doesn't change any of the substantive portions of the 1836 law. While the patent system was codified in 1952, there have not been significant changes in 140 years, notes Sen. Philip Hart (D-MI), a prime sponsor.
He says the bill will update the present antiquated administrative setup, provide for a more rigorous examination by the Patent and Trademark Office of patent requests, and require greater disclosure of prior art to that office by the applicant. Included in the measure are provisions for lowering and deferring fees to private inventors and small businesses.

Government's contracting procedures to be streamlined
The powerful Senate Operations Committee is now considering landmark legislation that would overhaul the Federal government's $70 billion a year contracting activities.
Introduced by Sen. Lawton Chiles (D-FL), S. 3005, "Federal Acquisition Act of 1976," is designed to legislate changes recommended by the . Commission on Government Procurement that couldn't be made administratively.
The bill "directly seeks to substitute effective competition for regulation" and is aimed at relieving a wide range of government surveillance, "but only where effective competition is at work," Chiles says.
A key provision requires the Office of Federal Procurement Policy to establish a single, simplified set of regulations to cover all agencies of the Federal government by meshing regulations generated by the Armed Services Act and the F(:lderal Property Act.
Other titles in the bill define the proper circumstances for agency use of acquisition procedures by competitive sealed bids, competitive negotiations (with an exception for single-source procurements) and acquisition by competitive small-purchase procedures.

Capital Capsules: NASA's Nimbus 6 meteorological research satellite gets a new task
thiis summer-tracking a Model-T Ford in the American Bicentennial Around-the-World Auto Race, an enactment of the Great Race of 1908. A 30-pound electronic package will be carried by a 1914 Model T to transmit the ground speed of the moving car to the Random Access Measurement System carried by the pole-to-pole orbiting satellite. . . . The Air Force has issued requests for proposals to 31 small business firms for a dual-bank radar beacon transponder set (AN/ TPN-28). The self-contained, portable 30-pound units are for forward air controllers. Contract award is set for midyear. The Air Force will buy 12 preproduction and 800 operational sets with the Marine Corps slated to get 340 of them.... The Navy has awarded Norden Div. of United Technology a development contract for a lightweight, high-frequency transceiver for shipboard use. The millimeter-wave communicator weighs 5 lb and offers voice, video or data transmissions over distances of up to 20 miles. Its narrow beamwidth minimizes interception.

44

ELECT RONIC D ESIGN 7, March 29, 1976

Dia light
sees a need:
Need: A new computer-grade switch at a price you can afford.

LOW COST· COMPUTER GRADE QUALITY· DESIGN FLEXIBILITY· GOLD OR SILVER CONTACTS· CHOICE OF TERMINALS· MOMENTARY OR ALTERNATE SWITCHING ACTIONS· SPOT, DPDT · DESIGNED TO MEET UL SPECIFICATIONS · UNIFORM FRONT PANEL APPEARANCE AND REAR PROJECTION · MATCH· ING INDICATOR LIGHT · FRONT MOUNTING SNAP-IN BEZELS-4 SIZES/SHAPES TO CHOOSE FROM · REAR MOUNTING SWITCH WITH ANTI-ROTATION FEATURE · CHOICE OF OVER 200 CAP SHAPES, SIZES AND COLORS· CHOICE OF ENGRAVED, HOT STAMPED OR REPLACEABLE LEGENDS.

Dialight's low cost 554 series switches are available in a wide selection of rear panel and front bezel mounting types. Switches are available with silver or gold contacts for wide range of applications; operating life is 250,000 operations.
Fingertip grips permit easy cap removal .·.

lamp replacement is from front of panel . . . no special tools needed.
Caps are available with or without underlying color filter in 5/s" and 3.4" square, 5/s" x 3.4" and 3.4" x l" rectangles. At Dialight it's your choice because we see your need.

DIAL/GI-IT
Dialight, A North American Philips Company 203 Harrison Place, Brooklyn, N. Y. 11237 (212) 497-7600
CIRCLE NUMBER 23

--~~ ~9

I

~-

-----. -

---. ---

--------

-------

I

46

TheTl990
computer family
has all the ingredients.
The TI concept of what a computer family should be goes beyond producing the most reliable and cost-effective hardware around. To us, that's basic. The extra dimension is usabil' ity, and this means software and support.
The TI 990 computer family has all the ingredients. We make every member ofthe family oµrselves, and we make them all software compatible from bottom to top.
Complete software libraries, as well as memory-resident and disc-based operating systems, support real-time and multi-tasking operations. We offer FORTRAN, COBOL and BASIC languages. Cross-support on timesharing networks allows early development of your own applications programs.
The TMS 9900 Microprocessor... The Technology Leader
The advanced capabilities of the 990 family result from a TI milestone in MOS technology... the TMS 9900 single-chip, 16-bit microprocessor. With its high-speed interrupt capability, hardware multiply-and-divide, and versatile instruction set, the TMS 9900 delivers the kind of computing power you'd expect from a 16-bit TTL computer. And it's the best microprocessor going for terminals, machine monitoring and control, and many other applications.
Because the TMS 9900 provides the instruction set for the new 990/4 microcomputer and 990/10 minicomputer, software developed for the low-end computers will be compatible with the higher performance models ... and with a minimum of interface and software adaptation.
Versatile Operating Systems
The TX990 Executive Operating System Software uses either the 990/4 or 990/10 computer for low-cost multi-task control, requiring a minimum of peripheral support. The modular construction ofTX990 allows users to select only the functions required for efficient memory usage, leaving more memory availa-
ELECTRONIC DESIGN 7, March 29, 1976

·

ble for application software. The 990/10 Disc System Software accents
the mass-storage, random-access features of the disc with extensive file management and the multi-tasking features of the DXlO Operating System. The system software package includes a multi-pass 990 assembler, link editor, interactive source editor, and numerous other utilities that support easy implementation of application programs.
Flexible Packaged Systems
TI offers two packaged program development systems and a prototyping system for the user who needs his own stand-alone system for software and firmware development of application programs.
These packaged systems provide a flexible method of implementing early project development. These include the low-priced 990/4 Program Development System and the powerful 990/10 Program Development System. The 990/10 system combines the power of the 990/10 minicomputer with the disc-based DXlO operating system and an extensive set of software development tools. The standard package includes the 990/10 minicomputer with 64K bytes of error-correcting memory, ROM loader and diagnostics, 3.1-million byte removable disc kit with accompanying peripherals, and a complete software development package. And, at $24,500, this system costs at least 20% less than comparable equipment from other manufacturers.
For developing firmware modules, there is a $5950 prototyping system which includes a 990/4 computer with 16K bytes of memory and programmer's front panel, and a "Silent 700*" twin-cassette ASR data terminal. Also, an optional PROM programming kit is available for

developing read-only memory. In addition, we provide a wide variety of
program development utilities for the 990 family. There is communications software that supports either synchronous or asynchronous data transmission, and can operate with the TX990 or the DXlO.

Support from the start

We offer complete training and applications

assistance, plus a nationwide service network

backed·by TI-CARE t, our remote diagnostic,

service dispatching and real-time field service

management information system.

For more information, call your nearest TI

office or write Texas Instruments Incorpo-

rated, P.O. Box 1444, M/S

~

784, Houston, Texas 77001.

Or, phone Computer

Equipment Marketing

at (512) 258-5121.

See the 990 Family at the Computer Caravan and NCC.
Arlington, Va. (703) 527-2800 · Atlanta. Ga. (404) 458-7791 · Boston, Ma. (617) 890-7400 · Chicago, II. (312) 671 -0300 · Clark, NJ (201) 574-9800 · Cleveland, Oh. (216) 464-4990 · Costa Mesa, Ca. (7 14) 540-7311 · Callas. Tx. (214) 238-5318 · Cayton, Oh. (513) 253-6128 ·Denver, Co. (303) 751 -1780 ·Detroit, Mi. (313) 353-0830 · El Segundo, Ca. (2I3) 973-2571 ·Hamden, Ct. (203) 28 I-0074 ·Houston, Tx. (7I3) 494.5115 · Indianapolis, In. (3I7) 248-8555 · Milwaukee, Wi. (4I4) 475-I690 · M inneapoli~ Mn. (6I2) 835·5711 · Mobile, Al. (205) 344-8082 · Ph iladelphia, Pa. (2I5) 628-3434 · Phoenix, Ai. (602) 249·I3I3 · San Francisoo, Ca. (4I5) 392·0229 ·Seattle. Wa. (206) 455-I711 ·St. Louis. Mo. (3I 4) 569-080I · Sunnyvale, Ca. (408) 732-1840 ·Winter Park, Fl. (305) 644-3535 · Amstelveen, Holland 020-456256 · Bedford, England 0234-58701 · Beirut, Lebanon 452010 · Bruxelles, Belgium 733.96.24 · Cheshire, England 061-442-8448 · Copenhagen, Denmark 01 /91.74.00 · Essen, Germany 0201120916 · Frankfurt, Germany 0611 / 39/ 90/ 61 · Freising, Germany 08161 / 801 · Helsinki, Finland 90-408 300 · Milan. Italy 02.688/8051 · Montreal, Canada (514) 341-5224 · Nice, France (93) 20.01.01 · Oslo, Norway 02-68.94.87 · Paris, France (I) 630-2343 · Rome, Italy 839.4792 · Slough, England 0753-33411 · Stockholm, Sweden 62 71 59/62 71 65 · Sydney, Australia 831·2555 · Tokyo, Japan (03) 402-6I8I · Toronto, Canada (4I6) 889-7373 · Vancouver, B.C. (604) 689-80I7

TEXAS INSTRUMENTS

*Trademark of Texas Instruments

INCORPORATED

tService Mark of Texas Instruments

CIRCLE NUMBER 24

ELECTRON IC D ES IGN 7, March 29, 1976

47

c

Diagnostic instrument simplifies µP-system testing and debugging

The first diagnostic instrument to combine thie features of both logiQ analyzerSI and µ,C -development systems can be used to simplify 8-bit µ.P-system testing and debugging. CaHed the MPA-1 Microprocessor Analyzer, it is produced by Motorola Data Products (455 E. North Ave., Carol Stream, IL 60187. 312-690-1400).
The MPA-1 cabinet and display typicaJly works in conjunction with a 40-pin IC test clip that clamps over the µP DIP package to lift address and data signals directly from the DIP mounting pins. The analyzer captures 32-word segments of program execution and di.splays t he information on a 9-in. CRT screen.
Words are shown directly in hexadecimal form, which allows direct comparison with written _program instructions, without the need for manual binary-to-hexadecimal translation. Each hex word consists of four characters of address, plus two characters of associated data-bus information.
By using individual probe buffers, the instrument can interface directly with the

following: the 8080 from Intel, Advanced Micro Devices, Texas Instruments and NEC; the PPS-4 from Rockwell; the 6800 from Motorola and American Microsystems; the 6500 from MOS Technology and Synertek; and Motorola's
( conti nued on page 50 )

Full microcomputer comes complete wi.th power supply

A ready-to-use, µ.P -based microcomputer, the Micro 68, comes complete with its own integral power supply and 16-button keyboard. A 6-digit LED display and 128 words of RAM are also included. The Micro 68 is built around the Motorola/ AMI 6800 µP, costs $430 and was developed by Electronic Product Associates (1157 Vega St., San Diego, CA 92110. 714-276-8911).
In addition, the 512 John Bug PROM that's included contains all the software necessary to load programs easily, inspect and edit them as necessary, insert break points for debugging, and to execute them. Memory expansion to 64 k and full 16-bit I / 0 can be accomplished through edge connectors.
The Micro 68 comes in a hardwood cabinet with a transparent smoked-plexiglass lid and measures 9 x 16 x 2 in. Delivery is from stock.
CIRCLE NO. 552

EL ECTRONIC DESIGN 7, March 29, 1976

49

MICROPROCESSOR DESIGN
(continued from page 49)
Exorciser system. The MPA-1 has three basic operating mode2.
In the Start Display mode, the instrument monitors program execution starting with the trigger-word address and adding the next 31 words in their order of execution. This allows the tracing of program flow, algorithms, interrupt-handling and l/O routines.
In the End Display mode, the MPA-1 can work backwavds from illegal operations to track down the source of hardware and software errors. And in the Free Run mode, continuous address and data information are displayed to locate hardware faults and program hang-ups. The instrument can be stopped in this mode; program execution can then be retraced to the source of a mistake.
Other features include Start Delayed Triggering, in which the 32-word display can
be delayed digitally up to 65-k clock pulses.
This feature allows examination of the inner workings of loops, the results of subroutine

caI!s and other uses in which desired data

does not immediately follow the trigger

word.

End Delayed triggering, with a delay of 16

clock cycles, provides a before-and-after

display in which the trigger word appears in

the center of the 32-word block, allowing

simultaneous examination of both preceding

and following µ,P activity.

, Besides the IC test clip, the instrument

is furnished with a standard 40-pin connecto,r

and a 40-connector cable. Also, at the rear

of the MPA-1 cabinet, two plugs allow

access to address-recognition and buffered-clock

signals for external counter or oscilloscope

triggering.

·

The MPA-1 package, complete with all

three probe connectors plus a choice of one oif

the available probe buffers, is priced at

$2985. Additional probe buffers cost $100

each. The MPA-1 cabinet measures 8 x 13 x

12 in. and weighs 24 lb.

CIRCLE NO. 551

Low-cost cross-assembler runs on IBM 360/370
A cross-assembler for the 8080 µP, designed to run on an IBM 360/ 370, is claimed to provide a low-cost alternative to the Intel MAC80 assembler available through time-sharing vendors. The MASM80 program is written in Fortran/ BAL and executes its operations in under 100 k of memory.
Well Test Data (P.O. Box 7081, Kansas City, MO 64113. 816-444-5519) is offering a source deck and documentation set for $55. Extra features of the MASM80 include direct punching of BNPF decks for PROM programming, object code listing in both octal and hex, and ASCII constant generation with the parity bit either set or reset.
CIRCLE NO. 553

µ P emulator offers fourfold increase in throughput

A microprocessor emulator that has from two to four times the throughput of the 8080 µP but is completely software-compatible has been designed by Technology Marketing Inc. (3170 Red Hill Ave., Costa Mesa, CA 92626. 714-979-1100).
Called the TMI 8080E, the emulator consists of 79 multiple-sourced ICs and occupies less than 80 in.2 of circuit board area. It requires just 180 ns for a machine cycle and is not as rigidly limited as the 8080 µP, in regard to memory timing.
A substantial advantage of the TMI 8080E, according to the firm, is that the 8080E can drive 10 TTL loads instead of the single-TTL load that can be driven by the 8080. In a system, this improvement in drive capability means that a large 64-k x 8-bit memory can be built into the system along with eight 1/ 0 modules, without additional buffering.
(continued on page 52)

50

ELECTRONIC DESIGN 7, March 29, 1976

Announcing a giant reduction in the Nova line.

®
You're looking at a whole new family of NOVA computers. microNOVA. A microprocessor chip, a microcomputer board and a complete MOS minicomputer. All based on the little thing on the tip of the finger.
mN601. The microNOVA CPU. It's a full-blown, 16-bit NOVA computer. Manufactured by Data General. And fully supported by NOVA software. And it's not a NOVA computer in name only. This chip has all the NOVA registers, internal data paths and computational elements. The NOVA multifunction instruction set. The NOVA multiple addressing modes. And the NOVA 3 hardware stacking. Plus things that used to be NOVA options: multiply/divide, real-time clock and power fail/ auto restart. All standard at no additional cost. The difference is, all that NOVA has been reduced to a single chip that measures only 225 mils by 244 mils. Which was no small accomplishment. For those who need more than a chip, there's the microNOVA computer-on-a-board. A complete, fully-buffered microcomputer that comes with 2K or 4K words of RAM on a sin_gle 7Yz" by 9Y2" board. You can add on more RAM in either 4K or

BK increments, or PROM boards with up to 4K

words. Plus terminal interfaces, general purpose interfacing boards, card frame, power supply and PROM burner.
And for those who need more than a board, there's a fully-packaged 4K word MOS microNOVA mini. It comes with power supply and turnkey console. In 9 and 18 slot versions. Into which you can_place as much as 32K words of RAM or

PROM. And still have plenty of room left over
for 1/0.
There's even a microNOVA system specifically

for program development. A complete system, with
dual diskette drive, terminal and our RDOScompatible Disc Operating ~stem. Or you can

use a Nova 3 system with ROOS. The best development software you can get.

And no matter which microNOVA product you get, you get to use NOVA software like FORTRAN

IV. Software that's in use in over 20,000 installations all over the world. So you know it's going to work right the day you get it.

Want to know something else?
NQI Call our toll free number. ·
nncro soo-225-9497.

TA 'VJ-\

Nova is a rcgistc~ trademark of Data Grncra1 Corporation.

DataGeneral
··Data General, Route 9, Southboro, Mass. 01772 (617) 485-9100. Data General (Canada) Ltd., Ontario. Data General Europe, 15 Rue Le Sueur, Paris 75116, France. Data General Australia, Melbourne (03) 82-1361/Sydney (02) 908-1366.

MICROPROCESSOR DESIGN

(continued from page 50 )
The emulator can cut system size when clock, bus driver, memory and .input/ output modules are added to the basic 8080 IC. The TMI 8080E single-board processor replaces the 8080 µP, the 8228 controller and bus driver, the 8224 clock generator, the 8216 bus drivers, and the associated circuitry.
The price orf the emulator starts at $1200 for a single-unit purchase, and prices drop · to $200 in production quantities. Delivery time is 6 to 8 weeks.
CIRCLE NO. 554

-System development tool works with PPS-8 µ Ps The Assemulator, a system-development tool, can help debug and develop 8-bit PPS (parallel-processing system) microcomputers. The new design aid permits real-time software check-out of systems with peripherals, and makes possible generation of ROM mask codes and encoding of PROMs and EAROMs for the field testing of prototypes. Designated the PPS-8MP, the instrument comes complete with software and comprehensive programming and operating manuals. It costs $3450 and was developed by Rockwell (3310 Miraloma Ave., P.O. Box 3669, Anaheim, CA 92803. 714-632-1650). PPS-8MP software consists of a ROM-resident supervisory program that provides utility and debugging functions, and RAM-resident assembly and text-editing programs. The assembly and text-editing software is supplied on tape and is loaded into the machine's RAM with a TTY, a TI 733 ASR tape reader, or an optional high-speed reader. Memory can be expanded in 2-k-byte increments to a total of 16-k bytes by internally adding RAM or EAROM modules. Even more memory can be added by using an optional bus extender or 8-k byte RAM module.
CIRCLE NO. 555

8080-compatible microcomputer uses bipolar logic for speed

Up to four times the speed of typical 8080 JLP-based systems is offered by a ·new

bipolar-based microcomputer, the System 80. It is fully compatible with the 8080 µP, can

be purchased with either core or semiconductor memory and has an extended addressing

capability of up to 1 megabyte of memory. The µC is made by Electronic Memories and

Magnetics (12621 Chadron Ave., Hawthorne, CA 90250. 213-664-9881).

Inside the System 80 is an asynchronous, MSI central processor, a minimum of 16-k,

8-bit words of read/ write memory, a direct-memory-access (DMA) capability, a ROM

bootstrap loader, an RS-232-C2 interface, an operator's panel and a five-slot chassis that

measures 5.25-in. high and has an integral power supply.

·.

Three basic speed/ memory configurations are available: the first is a core memory with

a 650-ns cycle time; the second is an NMOS semiconductor memory with a 450-ns cycle

time; and the third version is a high-speed NMOS unit with a 180-ns cycle time. Memory

capacities range from 16 to 64-k bytes on a single board. This approach allows the user

to set up a complete 256-k byte system in a 7-in. chassis.

Basic system prices begin at $4150 for 16-k bytes of core memory or $4500 for 32-k

bytes of semiconductor memory. Other semiconductor based systems offer 64-k bytes for

$5650, 256-k bytes for $14,000 and 1-M byte for $44,000. System 80s are available from

stock.

CIRCLE NO. 556

52

ELECTRONIC DESIGN 7, March 29, 1976

NOW! SINGLE IN-LINE RESISTOR NETWORKS WITH IMPROVED PERFORMANCE

BOARDABLE
ill~[])
AFFORDABLE

Low Cost and High Density Configuration
are only two of the features of Sprague Type 216C Metanet® Resistor Networks. Now, you can also enjoy the benefits of improved power dissipation, better temperature coefficient of resistance, and closer standard resistance tolerance.
Save Board Space. Single in-line design per-
mits vertical installation, which allows more units to be seated in less space. This mounting style also results in improved high-frequency performance and significant in-place cost reduction .
Better TCR. Typical temperature coefficient of re-
sistance is within ±200 ppm/°C, cutting previous allowable limit almost in half.

Up-graded Power Dissipation. Individual ter-
minating , pull-up/pull-down. and interface networks are capable of dissipating 250 mW per resistor at 70°C, an increase of 100% over previous designs.
Closer Resistance Tolerance. Standard re-
sistance tolerance for each resistor is ±2%. with other tolerances between ± 1% and ±5% available on special order.
Proven Product Line. Sprague has more than
fifteen years of experience in the development and manufacture of precision thick-film resistor networks, which include individual terminating, pull-up/pulldown, interface, and dual terminating designs.

For complete technical data, write for Engineering Bulletin 7041 A to: Technical Literature Service, Sprague Electric Co., 347 Marshall Street, North Adams, Mass. 01247.

THE BROAD-LINE PRODUCER OF ELECTRONIC PARTS

ELECTRON IC D ES IGN 7. Ma rch 29. 1976

CIRCLE NUMBER 27

4SZ-512 4RI
SPRAGUE .
THE MARK OF RELIABILITY
53

urcu

·

ra1

Ill

Advanced Micro Devices announces the 100piece price for the Am9080A and Am2901: $21.00.
Just like we said.

1975 PROJECTED PRICING FOR Am9080A and Am2901.
$35.00 -~-~--------

$30.00 1-------4----+---+---+---+------I

\ ? ~ $25.00 f-------~+-~---+-..1/.....____._-+--------I

~ $20.00

~

~ $15.00

~

1" $10.oo f----lf-----+---+L---"-!'o-..--+------1--~
$5.00 1-----+---+----+---+-~ -"'-.F1--=--=<

1975 1976 1977 1978 1979 1980 YEARS

54

ELI:CT RONI C D ESIGN 7, March 29, 1976

Last year, we predicted the price would be just over $20.00. We even drew a curve. Now it's happened. And that's only the beginning. Look:
Am9080A. It's built with an advanced ionimplanted, n-channel, silicon-gate process that permits versions with speeds to 250 nano-
seconds cycle time (one microsecond instruction time). Our low power (800mW maximum) gives you cooler running systems, less power drain and better reliability. The superior output drive (3.2mA @ 0.4V) gives increased design flexibility and improved margins.
Am2901. It's bipolar, for systems that rely on

high speed. It can do a 16-bit register-to-register add in just 145 nanoseconds. It has 16 working registers in a cycle-saving, two-address architecture, and is controlled by nine instruction lines that permit it to do almost anything you can think of.
Another thing. Advanced Micro Devices offers a full line of support circuits for either unit-support circuits that optimize your system, not compromise it.
Whether you can best use the MOS Am9080A or the bipolar Am2901, you can now do it for less. $21.00 in 100-piece quantities.
Just like the curve said.

Am9080A System Circuits

AMO Part Number
Am9080A/-2/ -1/- 4 Am9080A / - 2

Description
CPU
Speeds to 250 nsec O to 70°C Speeds to 380 nsec -5 5 to + t25°C

Availability
In Dist Stock In Dist Stock

Static Read/ Write Random Access Memories

Am9101 A/B/ C/ D Am91 L01A/B/ C Am9102A/ B/C/ D Am91 L02A/ B/ C Am9111 A/B / C/ D Am91L11 A/B/ C Am9112A/ B/C/D Am91L12A/ B/ C Am9130A/ B/C/E Am9140A/B/C/ E

256 x4 Speeds to 250 nsec
256x4 Speeds to 300 nsec
1Kx1 Speeds to 250 nsec
1Kx1 Speeds to 300 nsec
256x4 Speeds to 250 nsec 256x4 Speeds to 300 nsec
256x 4 Speeds to 250 nsec
256x 4 Speeds to 300 nsec
I 024x4 Speeds to 200 nsec
4096x 1 Speeds 10 200 nsec

In Dist Stock In Dist Stock In Dist Stock In Dist Stock In Dist Stock In Dist Stock In Dist Stock In D1s1 Stock In Dist Stock In Dist Stock

Dynamic Read/ Write Random Access Memories

Am9050C/ D/ E Am9060C/D/E

4Kx 1 Speeds to 200 nsec
4K x1 Speeds to 200 nsec

In Dist Stock In Dist Stock

Mask Programmable Read-Only Memories

Am9208/ B/ C/ D Am9214 Am9216B/ C

1Kx8 Speeds to 250 nsec
512x8 mask programmed Speeds to 500 nsec
2Kx8 mask prog rammed Speeds to 300 nsec

Available Now Available Now Available Now

Erasable Read-Only Memories

Am9702 Am1702A Am2708

256 x8 Speeds 10 1 0 11sec
256x8 Speeds to I O µsec
1024x8 Speeds to 450 "sec

In Dist Stock In Dist Stock 2nd 0 1976

AMO Part Number
Am8212 Am8224 Am8228 Am8216/ 26 Am25L5138 Am9555
Am9551

Description
Processor System Support Circuits
8-b1t 1/ 0 Po rt Clock Generator System Controller Bus Transceiver I of 8 Decoder Programmable Peripheral In terface Serial Commun1ca t1ons In terface

Availability
ln Dist Stock In Dist Stock 2nd 0 1976 2nd 0 1976 In Dist Stock 2nd 0 1976
2nd 0 1976

CPU 9080A = 480 nsec - 2=380 nsec 1= 320 nsec 4 250 nsec

Mem

A= 500 nsec B= 400 nsec C = 300 nsec D - 250 nsec E= 200 nsec

Am2900 System Circuits

AMO Part Number Am2901 Am2902 Am2905
Am2906
Am2907
Am2909 Am2911 Am2914 Am2915 Am2916
Am2917
Am2918 Am2919 Am2950/ 51
Am2952 Am2954/ 55
Am2970/ 71

Description

Availability

4-Bit Microprocessor Slice Carry Lookahead Chip 4-Bit Transceiver For Open Collec1or Bus 4-Bit Transceiver For Open Collector Bus Wi th Par11y Generator/Checker 4-Bit Transceiver For Open Collector Bus With Single Data lnpul
Microprogram Sequencer M1n1m1croprogram Sequencer
8-Level Priority In terrupt
4-Bit Transceiver For Th ree-Sta ie Bus 4-Bit Transceiver Fo r Th ree-State
Bus With Parity Generatof/Checker 4-Bit Transceiver For Three-Staie Bus With Single Data Input 1 By 2 Port Register
Priority Interrupt Expander 256 Bit RAM Open Collector Or Three -State I 024 -Blt RAM Open Collector 16-Word By 4-Bit Two Address Register Stack . Open Collecto r or Three-State 256 By 4 PROM s With Open Collector or Three-State Outputs

In Dist Stock In Dist Stock In Dist Stock
In Dist Stock
In Dist Stock
In Dist Stock 2nd 0 1976 3rd 0 1976 2nd O. 1976 2nd 0 1976
2nd 0 1976
In Dist Stock 2nd 0. 1976 In Dist Stock
2nd 0 1976 2nd 0 1976
In Dist Stock

Advanced Microprocessors
~

Ad vanced Mic ro Devices · 90 1Thompson Place, Sunnyvale , Cal1forn1a 9 4086 · Telephone (408) 732-2400

Distributed nationally by Hamilton/Avnet, Cramer and Schweber Electronics

CIRCLE NUMBER 28

EL ECTRONIC D ESIGN 7, March 29, 1976

55

There is no more accurate 12-bit AID converter on the market ··· and it's monolithic.

Differential and overall linearity within V2 LSB. Inherently monotonic operation (and no missing codes) . Immunity to noise transients. They all add up to unusually high accuracy for our 8702 , a single chip , 12-bit CMOS A/D converter.
The 8702 has some other important advantages , too. CMOS technology means very low power dissipation - typically less than 20 mW . It is easy to use ; no active auxiliary components are needed . And its latched parallel outputs are

ideal for inputting to microprocessors or other digital logic.
Compared to modules , the 8702 offers immediate significant cost sav ings plus the prospect of even greater future economies due to its monolithic construction. And the savings in PCB real estate go without saying .
The 8702 comes in a 24-pin ceramic DIP . 8 and 10 bit versions are also available. Call or write for the full details today.

.._~TELEDYNE SEMICONDUCTOR

1300 Terra Bella Avenue. Mountain View , Cal1for11ia 94043 Tel: (415) 968-9241TWX : 910-379-6494 Telex : 34-8416 SALES OFFICES o DOMESTIC : Salem, N.H. (603) 893-9551; Stony Brook, N.Y. (516) 751-5640; Des Plaines. IL (312) 299-6196: Los Angeles, CA (213) 826-6639; Mountain View, CA (415) 968-9241 · INT ER NAT I ONA L: Hounslow, Middlesex. England (44) 01-897-2503; Tiengen. West Germany 7741-5066; Wiesbaden . West Germany 06121-39171 ; Kowloon. Hong Kong 3-240122 ; Tokyo . Japan 03-405-5738

CIRCLE NUMBER 29

56

E u .C'T RON JC' D1: S IGN 7. Ma rch 29. 1976

If I·don't know it, it ain't so
A friend of mine had intermittent claudic:ation-a blood-vessel constriction that afflicts many heavy smokers and often leads to amputation. He took massive doses of vitamins and was cured. Another fellow's kidney stones were eliminated by vitamins. And vitamins helped other friends with ailments like high blood pressure, high cholesterol , low energy, headaches, colds, bleeding gums and bursitis.
The average doctor, or the American Medical Association, or the Food and Drug Administration will likely tell you that beyond the nutrition you get in a reasonably balanced diet, \·iLamins don 't really help. Their attitude seems to be that vitamin-deficiency diseases have been licked; nobody gets scurvy or beri-beri anymore; a massive vitamin deficiency can hurt you, but a less-than-massive deficiency has no effect.
If you ask about people who've been helped by vitamins, you get a stock answer; they probably would have gotten better anyway. But what they really mean is probably this: The authorities don't support it, so it can't be so.
And that attitude is too common. Most of us too quickly say, "That can't work. I never heard of it." Even in a profession where we take pride in our creativity, we remain conservative. We shy away from the untriedfrom material we didn't learn in school or books, and from ideas that don't carry the seal of authority.
It's unfortunate that a powerful precedent for this attitude is set by doctors-whose wisdom and infallibility many of us regard with awe. Doctors, when they don't kill their mistakes, often forget them. For many years they ridiculed the idea that thalidomide could be dangerous. Then overwhelming evidence showed that it mangled unborn babies. And for years the Food and Drug Administration insisted that Red No. 2, which appears innocuously on labels as "artificial coloring," is harmless. The FDA finally conceded that the stuff-widely used in foods, drugs and cosmetics-can cause cancer.
If prestigious authorities like medical doctors and the FDA scoff at ideas that differ from the accepted "wisdom,'' shouldn't we? Should we cling always to what's safe? Or should we sometimes break away and accept the scorn of authorities?
GEORGE ROSTKY
Editor-in-Chief

ELECTRONIC DESIGN 7, March 29, 1976

57

While diversity usually makes a designer's life easier, with microw processors it can make --------comparison-not to mention selection-more difficult than ever.
A wide diversity of architectures, support circuits and design aids from availaible µPs should
make it a whole lot easier to pick the right micro.
But because microprocessor-based systems must be programmed like conventional computers, you must think of software as weU as hardware. Grappling with the intricaJCies of either could keep you working evenings and weekends, especially since the use of different micros entails different tradeoffs between hardware and software.
Further, the problems of selection may not be helped much by the burgeoning application literature offered with "computers on a chip." You could end up with documentation up to your eyeballs only to discover that key specifications have been inflated or even omitted or that some important c.hJaracteristks~like operating speedcan't be extrapolated from the mountain of data. Adding to the problems, manufacturers' promotional material may elevate a selling point into an unwarranted .selection factor. The prices of microprocessor, or CPU (central processing unit), chips are a case in point.
Manufacturers note that the high-flying 8080 µP, for example, can be purchased now for about $20 in production quantities-quite a drop from its initial price of several hundred dollars. For very high quantities, you can get the price under $10.
But a CPU chip itself is about a.s useful a.s a pet rock. For a complete, operating µC (microcomputer), you must add peripheral and interfaJCe circuits, as well ais memory. A simple µC-
Edward A. Torrero Associate Editor
58

A data-processing controller resides on a PC board meas-
uring only 4-1/2 x 4-1/2 in. The board combines
National Semiconductor's Pace (the first single-chip 16bit µP) with sense amplifiers, hex buffers, a crystal oscillator and clock drivers.
ELECTRONIC D ESIGN 7, March 29 , 1976

based controhler could require at least 25 extra chips surrounding the processor. The cost of the additional components exceeds the price of the CPU by a wide margin. Moreover, a package of system components having. an attractively priced CPU may have an over-ali"cost that's higher than one that doesn't.
Whatever the system hardware's cost, it is likely to be dwarfed by the soaring cost of µC software, which can range from hundreds of dollars to thousands for the finished system. For a $30 µP, sucih software has been known to cost niore than $65,000.
Of course, your software development is a "one shot" expense that can be amortized over the life of the product--assuming it is a successful one. But should you decide to switch micros, you won't be able to transfer a design using the first µP's software to the second. The experience gain-
The most advanced development system for micros, Intel's MDS (microcomputer development system), features in· circuit emulation. The capability permits early fault and error isolation in system prototypes. MDS includes flop· py-disc storage and a CRT terminal, and allows the setting of breakpoints symbolically.
A single-chip 16-bit ,µP is the latest offering from Texas Instruments' growing line ot microprocessor products. The new TMS 9900 µP is upward compatible in software with other members of the 990 processor family, which includes a minicomputer. ELECTRONIC D ESIGN 7, March 29, 1976

ed from one µ,P can't be applied to another. Different micros come with different software capabilities, hardware requirements and design aids. That fir.st costly system may have to be scrapped completely.
µP products and technologies: a mixed bag
Microprocessors and related circuits can be obtained in a variety of technologies and product forms. Older micros employ p-channel MOS (PMOS) and offer 4, 8 and 16-bit word lengths. The bulk of p'resent MOS micros uses speed-enhancing n~channel MOS (NMOS) for 8-bit units and specifies a basic cycle time of about 2 µs. More recently, NMOS has been applied to 16-bit µPs and power-saving complementary-MOS (CMOS) has been used to buHd 8 and 12-bit µ,Ps.
Product forms encompass just about anything .you'd care to ask for, from a sack of parts to a µP-based minicomputer. At the simplest level, you can purchase a set of chips that include the CPU, special interface ICs and, generally, special memories. If you don't want to be bothered testing, mounting and .interconnecting the chips, you can purchase a logic board instead. The ,µP-based board comes fully wired and ready to run, although at the very least you generally have to provide system-test equipment and a power supply.
At the high end of the price ladder are comP·lete µP-based development systems, such as Intel's MDS (microcomputer development system), Motorola's Exorciser and National Semiconductor's IMP-16. These units constitute sophisticated hardware/ software design aids that offer the conveniences and peripherals associated with minicomputers-at prices to match. A bas.ic system starts at about $5000 and rapidly escalates to about $10,000 if you decide to use sucli system peripherails as a ftoppy-disc operating system, video terminal and PROM programmer.
Currently the most popular product form for microprocessors is the do-it-yourself kit. Priced at $500 or less, the µ,P kit offers designersespecially the growing number of newcomersan inexpensive and fairly painless way to get a ,µP system up and running.
However, like the microprocessors they are built around, kits may not live up to all the claims made for them. IdeaJ.ly a kit should be easy to use aind allow some system prototyping. But whether the kit actually does these things often reveals what was left out to keep prices low, even better than it reflects what was put in. The old adage, "you get what you pay for," might well be applied here.
One kit may be priced significantly lo·wer than another, though both use the same microprocesso·r
59

and offer about the same features. Sometimes the difference in price is due to the use of less expensive ICs in the lower-priced model. These ICs exhibit temperature and voltage limitations that aren't necessarily bad for home experiments, but which could prove disastrous in an industrial environment.
All kits require hand-assembly for program entry. Instructions must be entered one bit at a time, though some units feature hex or octalcode entry, thereby shortening the number of times you have to move a switch or press a button. Manual assembly may not be a problem if your program isn't longer than a few hundred words. But it rapidly becomes unwieldly for a program any longer than that-assuming the kit has sufficient memory to store it.
What you can prototype with a kit depends largely on how much memory comes with it. Capacity ranges from 256 bytes up to 8-k, though most units don't have more than about 1-k of storage. The capacity is sufficient for simple systems.
But storage capacity can easily become a problem for applications that need 1000 or more words of code-like a computer-peripheral controller. Moreover, long programs can't be debugged easily. A hand-assembled program that has errors has to be redone completely, unless spaces (No Op instructions) have been left in the program for corrections.
The most serious problem arises when the set of components doesn't come with adequate monitor and debug programs. A monitor program provides the means to drive a control panel or operate the system through a teletypewriter. A debug program lets you single-step the system one instruction at a time, examine memory, and insert breakpoints. Typically, the monitor and debug programs are combined in ROM and offered as firmware.
Without these essential programs, that µP system does little more than talk to itself. Of course, monitor/ debug software can be developed. But presumably you bought a kit because you wanted to learn about microprocessors the easy way.
Chip sets reduce package count
Newer µP-chip sets have overcome one of the most serious shortcomings of early µPs-the need for a host of supporting chips to interface with peripheral devices, data-communication lines and even the µP's own memory. The first 8-bit µP and the only one for about two years-Intel's 8008required 20 or so additional standard-TTL circuits to make .it work.
Constrained primari,ly by the limitations of an 18-pin package, the 8008 needed the following: registers to address memory, either ROM or
60

Features often associated with minis combine with the ease·of·use of other programmable controllers in the Eptak industrial-control system from Eagle Signal. The system uses the 8080 µP.
The 6800 µP forms the nucleus of an 8-bit microcomputer chip set that includes a peripheral-interface adapter and an asynchronous-communications interface circuit. Introduced by Motorola, the chips have been alternatesourced by American Microsystems and Hitachi .
RAM; decoders to interface with memories; other ICs to handle ,µP information and to synchronize the operation of the µP and the support circuits; clock circuits; and a number of interface ICs, depending on the application. For example, in a multichannel data-communications application,
each channel requires an asynchronous receiverI
transmitter and associated interface ICs.
ELECTRONIC DESIGN 7, March 29 , 1976

Now improved µPs like Intel's 8080, Motorola's 6800 .and Fairchild's F8 have come along. Special LSI peripheral and memory cirouits match and enhance the µPs they support. Together with improvements in the CPU chips, the resulting chip sets constitute minimal-chip configurations that can drastically reduce package count while improving performance.
But even new chip sets may not be all they seem. Some manufacturers stress the fact that their µP systems can run from TTL levels of 5 V and ground. However, more than a single supply may be needed if you decide to use such memories as some of the new 4-k dynamic RAMs, or some PROMs. Also, you'll need another supply if you want to hook up a device that spits out ASCII characters, or more simply, if you try to provide the µP's demanding olock requirements with conventional circuitry.
Expansion can present other problems. Since many chip sets employ nonstandard memories, you're limited in the choice of storage elements, even though the manufacturer claims that any memory works well with the µP-including core, though that admission may have to be pulled out of a semiconductor manufacturer. In some cases, you can use the memory of your choice, but only after you've added special memory-interface ICs to your "minimal" chip system. And if the memory i:s static, you might use a different interface chip than the one for a refresh-hungry dynamic memory.
Further, several chip sets employ mask-programmable ROMs for program storage. These can be found in such MOS µPs as those that employ bit-slice configurations, as well as those that incorporate the control memory within the CPU circuits. In such cases, your system-development time will have to include the manufacturer's turnaround time for ROM mask programming.
An obvious time-saving solution would be to employ PROMs, especially the erasable kind, as a growing number of designers are now doing. But again, these components can entail additional circuitry and power supplies.
For situations that do entai·l additional circuits, manufacturers provide an ever expanding line of package-saving MSI (medium-scale-integration) circuits. Unlike key LSI peripherals, though, the MSI units aren't always an economical buy. You do save on, sa.y, a complex dataoommunications chip or a direct-memory-access controller that rep,laces. 10 or more standard-TTL circuits, but you won't always save with an MSI component that replaces just a few standard packages. The best bet is carefully to select the components you want in a manufacturer's µ,P family and consider making up the rest with standard TTL.
Shop around, too, for the best price tag on the
ELECTRONIC DESIGN 7. March 29, 1976

same component. It wasn't always possible to do so when µ,Ps were virtually sole-source products and typically were offered only as part of complete chip-package orders and only when you purchased the associated memory from the same IC manufacturer. That practice has since died down, mainly because of falling memory pdces. But several designers report they still encounter it. If you find this problem, go to an alternate source.
Avoid specification pitfalls
Though microprocessors are far too complex to be characterized by a simple data sheet, spscifications for µPs do abound. Ideally one should be able to use the published data to make a s3lection. However, spec sheets don't ail.ways reveal what a ,µP will do, or how it will react in your application.
A widely omitted spec is noise immunity, even
A single-board microcomputer based on the 80801ntel 's SBC 80/ 10-features 48 lines of programmable I/ 0. The board includes 4-k bytes of ROM and 1-k byte of EPROM.
though manufacturers promote their products as ideal for use in industrial equipment. For some ifLPS, the omission may be intentional. A comparison between input levels for peripheral circuits and the address-output levels of the µP may show little or no protection against unwanted transients.
However high noise immunity specs can be expected from newer microproc~ssors. For example, CMOS µPs from Harris Semiconductor, Intersil and RCA excel in no,ise immunity-a forte of the low-power technology.
If you don't have the noise immunity needed, you'll quickly discover the fact when you move from a clean, noise-free bench to a production environment. Of course, the problem can be overcome with simple level shifters and pull-up resistors. These components are cheap., but they do take up valuable board space and drive up power dissipation.
Another spec that's hard to find is the length of time the µP will hold data from a memory
61

after Write signals have dropped. Some memories, especially the most inexpensive, can't work with a µP unless they hold data for, say, 100 ns. Too low a hold time results in data loss. Without the holdtime spec, memories added to the system may have to be selected by trial and error.

~

·

· .......

1 ...

. 0

l'I

.._ ' ~

Speed specs confuse
Of the specs that are generally published, few a.re more numerous than the ones offered as a measure of a microprocessor's operating speed. A typical data sheet specifies a basic cycle (or mic;rocycle) time, state time, clock rate, execution time, interrupt time, and time to add two decimal numbers, among other "times." Para,. doxically, none of these nor any combination gives either a complete measure of a µP's computing speed, or fully tells how much work the ~p can do in a unit of time.
Consider cycle time-possibly the most useless measure, though most of the others could lay a strong claim to that distinction. Many microcomputer operations require several cycles to be performed. This is especially true of the more powerful instructions, which take far more time than the basic cycle indicates. Further, it's very possible for one µP with a seemingly high clock rate to perform a fundamental operation-like register-to-register add-more slowly than it is performed in a unit with a slower clock.
In a comparison of different µPs, differences in architecture and chip design tend to minimize the importance of specs like clock rate and cycle time. Moreover, all of these time specs don't measure such critical times as the over-all time needed to perform important routines. Not accounted for are additional delays, particularly those needed to obtain information from memory.
For example, one spec sheet says that a Call instruction for a subroutine takes about 11 states for execution. Since each state takes about 1/ 2 µs, the Call instruction should be completed in less than 6 'f"S· However, memory must be referred to five times before the instruction is completed, and each reference typically a.dds an additional state time since few memories are sufficiently fast. So a Call can easily take significantly longer than expected.
Often the number of instructions is spotlighted as an indication of the µP's prowess. There are several reasons why this emphasis can lead to fallacious comparisons. A number simply doesn't reveal what instructions are available for data movement and manipulation, for decision and control, or for I/ 0 operations.
Nor does a number tell which instructions are single or multibyte in length. Double-byte instructions take twice the memory of single-byte
62

One of the first development systems to use the 8080, Process Computer Systems ' Micropac 80 /A simplifies the design of controllers for industrial equipment.
instructions. And missing instructions can always be made up with additional hardware or with software routines, although the latter sacrifices speed. Further, a µ,P that features a number of addressing modes allows tighter and more efficient coding than a ~p with more limited addressing capabilities.
Sometimes the number of available µP instructions depends on whkh page of the applications manua.l you're reading-because the manufacturer has multiplied instructions. The multiplying factor may be the number of addressing modes or the number of registers (in, say, a load-to-register operation), or the number of conditions (for example, those on which a branch may occur). Other multiplying factors may be used, so that one or more parts of the original instruction set might be multiplied several times. · Improved instruction sets do come with longerword-length µPs and with advanced versions of older units. For example, 16-bit models can handle multiplication or division with a single instruction. In 8-bit µPs, these functions call for either subroutines or special circuitry.
Further, advanoed µPs offer the original instruction .set of a predecessor, and more powerful instructions, too. However this "software com.patibility" doesn't allow routine upgrading of systems by chip replacement. And a pin-compatible higher-speed version of a µP doesn't produce a faster, more efficient system unless there are some design changes first. In general, expect to redesign if you want to employ the new hardware/ software tradeoffs efficiently.
Programming ease: a key selection factor
A microprocessor's instruction set and architecture determine one of the most frequently stressed selection factors-programming ease.
Programming can be very time consuming. Various estimates place the number of lines of "shippable" code that a programmer can write in a day at less than 20 because of the time needed to write the program, run it, and then to debug,
ELECTRONIC DESIGN 7, March 29 , 1976

check and finally document the code. However, microprocessor-chip designers are
constrained by limitations of technology and packaging; their chips must fit into a package no larger than a 40 or 42-pin DIP. As a result, e~ch µ,P reflects a very different series of compromises and tradeoffs. Though each manufacturer says his ,µ,P is easy to program, the programmer is actually both helped and hindered by each ,µ,~. ~he degree of each depends on the specific apphcat10n involved.
For example, one µ,P's instruction set may seem to be quite complete. It has a fine complement of test and branch instructions, all the logic instructions you need and all the memory-reference instructions you could possibly require.
But the ,µ,P doesn't allow program-r~lative addressing, though most other addressmg modes are available. If you are writing a large program -as more and more microcomputer designers are -you can't easily relocate a ROM-based program from one memory-address space to another. So design changes may require a redoing of the program.
Another µP may allow the memory-addressing mode as well as indirect and indexed addressing, but at the expense of no direct addressing-the most common type. In this case, you'll be able to move programs around, but you won't be able to address all of memory without detouring through the index register.
Benchmarks get mixed reviews
One solution to the problem of comparing chaotically different µP.s is the use of benchmarks. In theory, these short test routines show how well different µ,Ps perform critical tasks, like moving data from one part of memory to another. These software tests, adherents argue, provide a quick and easy short-cut to the one · obvious but unwieldly solution: writing complete, optimized programs for different µPs and comparing results.
In practice, though, different benchmarks from different µP manufacturers show that each has a better product than anyone else. And a benchmark test that puts one JILP on top of the heap can be modified ever so slightly so that the pacesetting µ,P loses out to others. For example, one manufacturer provides a benchmark test that show.s its unit is the best mover of data in a µ.P's memory. But if that pace-setting micro must also deal with an interrupt during data-move operations, it falls far behind the pack.
Benchmarks designed for one particular architecture can be thoroughly ineffe tive for another. If you're doing a job that requires 16 bits of precision for the job, then a 16-bit µP will out-dis-

The FB two-chip set consists of a CPU and a programstorage unit. The CPU (above) contains a 64-byte scratchpad, eliminating the need for RAM in many applications. When needed, though, external RAM can be· added to an F8 system. Introduced by Fairchild, the F8 is also available from Mostek.
taince 8-bit versions. When many different opera-ations need to be performed a multiregister ~p .wiU outperform one with fewer available registers. For any model, no software test reveals the hardware side of the story-the required support circuits and necessary power supplies, for example.
And for a number of applications, benchmark tests may be just plain meaningless. In a host of µP applications, the micro may spend much of its time waiting for some external event, like the closing of .a switch or the pressing of a button, that can take milliseconds just for the contact bounce to die down. A test that merely compares sub-millisecond operating speeds has little relevance to this problem.
Still, benchmarking provides meaningful results when used to compare two slightly different versions of the same system. The difference might be the use of a somewhat altered µ,P, or a modified I/O scheme. In other cases, design the benchmark to the specific application or task at hand. If you're presented with comparative benchmark tests, be sure they are specified completely. ··
Need more information?
For additional information on specific products, circle the appropriate information retrieval numbers. For data sheets on many microprocessor and related products, consult ELECTRONIC DESIGN 'S GOLD BOOK.
AEG-Telefunken, 6 Frankfurt 70, AEG-Hochhaus, Germany. Circle No. 501
(continued on page 64 )

ELECTRONIC DESIGN 7, March 29, 1976

63

...

·'··

~· ··
..
.:

r continued from page 68)

Nurl-loC
... 4-way
problem solver
Warp ... only the patented Nurl-Loc® design, with 500% more gripping surface, eliminates panel warp by spreading stress. Spin ... gear-locking action guaranteed not to rotate during wrapping. Tear ... replace terminals up to 3 times without tearing or crazing panel. Snap ... no brittle pins to break. Accurate true position without pin straightening. Interested? Call Allan Klepper (401) 769-3800 or contact Electronic Molding Corp., 96 Mill Street, Woonsocket, Rhode Island 02895.
c

Adaptive Systems, P.O . Box 1481, Pompano Beach, FL 33061.

(305) 942-4000.

Circle No. 502

Advanced Memory Systems, 1275 Hammerwood, Sunnyvale,

CA 94086. (408) 734-4330.

Circle No. 503

Advanced Micro Devices, 901 Thompson Pl. , Sunnyvale, CA

94086. (408) 732-2 400.

Circle No. 504

American Microsystems, 3800 Homestead Rd., Santa Clara,

CA 95051. (408) 246-0330.

Circle No. 505

Applied Computing Technology, 17961 Sky Park Circle, Irvine,

CA 92707. (714) 557-9972.

Circle No. 506

Burroughs, P.O. Box 517, Paoli , PA 19301. (215) 648-2000. Circle No. 507

Computer Automation, 18651 Von Karman Ave., Irvine, CA

92664. (714) 833-8830.

Circle No. 508

Comstar Microcomputers, Warner & Swasey, 30300 Solon In· dustrial Pkwy., Solon , OH 44139 . (216) 368-6200. Circle No. 509

Data Works, 9748 Cozycroft Ave., Chatsworth, CA 91311. (213)

998-8985.

Circle No. 510

Digital Equipment Corp., 146 Main St., Maynard, MA 01754.

(6 17) 897-5111.

Circle No. 511

Eagle Signal Industrial Controls Div., Gulf and Western , 736
Federal St ., Davenport, IA 52803 . (319) 326-8101. Circle No. 512

Electronic Arrays, 550 E. Middlefield Rd. , Mountain View, CA

94043. (415) 964-4321.

Circle No. 513

Essex International, 564 Alpha Dr., Pittsburgh, PA 15238.

(412) 782-0200.

Circle No. 514

Fairc h i ld Semiconductor, 1725 Tec hnology Dr.. San Jose , CA

95110 (408) 998-0123 .

Circle No. 515

Fujitsu, 2-chome 6-1, Chiyoda-ku Tokyo, Japan . Circle No. 516

General A11tomation, 1055 S. East St., Anaheim , CA 92803 .

(714) 778-4800.

Circle No. 517

General Instrument, 600 W. John St.. Hicksville , NY 11802.

(516) 733-3000.

Circle No. 518

Harris Semiconductor, P.O. Box 883 , Melbourne , FL 32901.

(305) 727 -5407.

Circle No. 519

Hitachi, 23-15 6-Chome, Minamiohi , Shinagawa-ku, Japan. Circle No. 546

Intel, 3065 Bowers Ave ., Santa Clara , CA 95051. (408) 246-

7501.

Circle No. 520

lntersil, 10900 N. Tantau Ave., Cupertino, CA 95014. (408)

25 7-5450.

Circle No. 521

Martin Research, 1825 S. Halsted St., Chicago, IL 60608.

(312) 829-6932 .

Circle No. 522

Microcomputer Associates , P.O. Box 304, Cupertino, CA 95014.

(408) 226-3191.

Circle No. 523

MITS, 6328 Linn Ave., Albuquerque, NM 87108. (505) 265·

7553.

Circle No. 524

Monroe Calculator Co ., 550 Central Ave ., Orange, NJ 07051.

(201 ) 673-6600.

Circle No. 525

MOS Technology, 950 Rittenhouse Rd ., Norristown , PA 19401.

(215) 666-7950.

Circle No. 526

Mostek, 1215 W. Crosby Rd., Carrollton , TX 75006. (214) 242 -

0444.

Circle No. 527

Motorola Semiconductor, 5005 E. McDowell Rd., Phoenix, AZ

85036. (602) 244-3 465.

Circle No. 528

Multisonics, 3300 Crow Canyon Rd., P.O. Box 350, San

Ramon, CA 94583 . (415) 837-8111.

Circle No. 529

NEC Microcomputers, 5 Militia Dr.. Lexington, MA 02173.

(617) 862-6410.

Circle No. 530

National Semiconductor, 2900 Semiconductor Dr., Santa Clara,

CA 95051. (408) 732-5000.

Circle No. 531

Panafacom, P.O. Box 4637, Mountain View, CA 94040. Circle No. 532

Pl~s2s7e65 . ~;%)s~~\;'.'gg5]9 .1674 McGaw Ave ., s~7~~le A~~'. 5~~

Process Computers Systems, 5467 Hill 23 Dr., Flint, Ml 48507.

(313) 767-8920.

Circle No. 534

Pro-Log, 852 Airport Rd ., Monterey, CA 93940. (408) 372-4593. Circle No. 535

RCA , Route 202, Somerville, NJ 08876. (2 01 ) 722-3200. Circle No. 536

Rockwell International, Microelectronic Device Div., P.O. Box 3669, Anaheim . CA 92803. (714) 632-2321. Circle No. 537

SEMI, Div. of EM&M , 3883 N . 28 Ave ., Phoenix, AZ 8 5017.

(602) 263-0202.

Circle No. 538

Signetics, 811 E. Arques Ave., Sunnyvale , CA 94086 . (408)

739 -7700.

Circle No. 539

Sy nertek, 3050 Coronado Dr., Santa Clara, CA 95051. (408)

241-4300.

Circle No. 540

Tel edyne Systems, 19601 N. Nordhoff St.. Northbridge, CA

91324 (2 13) 886-2211.

Circle No. 541

Texas Instruments, P.O. Box 1443, Houston, TX 77001. (713)

494-5115.

Circle No. 542

Toshiba Transistor Works, 1-Komukal, Toshiba -Cho, Kawasaki -

Chi , Japan.

Circle No. 543

Western Digital, -19242 Red Hill Ave ., Newport Beach , CA

92663. (714) 557-3 550.

Circle No. 544

Zilog, 170 State St., Los Altos, CA 94022 . (415) 941-5055. Circle No. 545

CIRCLE NUMBER 30
64

ELECTRONIC D ESIGN 7, March 29 , 1976

Out of almost 30,000
flexible circuits···

This circuit is critical in the operation of a sophisticated plasma display unit. Somebody else said they could make it cheaper.
They did. And the customer's reject rate shot up over 1000 times.
Now, BMC is producing it again with the same reliability as before. Sure, it's costing our customer a little more at the beginning. But, he saves a lot in the end.
Because after almost 20 years of experience in flexible circuitry we know what it takes to build in reliability. Like almost constant inspection .

We inspect the raw materials. The photo sensitized laminate. The imaged laminate. The plated circuit. The coverlay. The finished circuit.
Every step of the way skilled BMC craftsmen have written specifications that must be met. Extra care and attention that may cost a little more.
But, we can show you at least one customer who thinks it's worth every penny. Wouldn 't you pay a little more for that kind of reliability?
For more information, contact Ed Dugan, Circuits Division , (612) 228-6371.

only4were reJ· e

CIRCLE NUMBER 31

THE SPECTROL MODEL 534 Standard, 10-turn, wirewound Model 534 - 100-piece price, $4.75. Also offered as standard, 5 and 3-turn models. Send for a data sheet, or call for a quote.
SPECTROL ELECTRONICS GROUP UNITED STATES Spectrol Electronics Corporation 17070 E. Gale Avenue, City of Industry, Calif. 91745, U.S.A. · (213) 964-6565 ·TWX (910) 584-1314 UNITED KINGDOM Spectral Reliance Ltd. Drakes Way, Swindon, Wiltshire, England· Swindon 21351 ·TELEX: 44692 ITALY SP Elettronica spa Via Carlo Pisacane 7, 20016 Pero (Milan) Italy· 35 30 241 ·TELEX: 36091
CIRCLE NUMBER 32

..M. l ~

USE THIS FOR

I I I

tl:oI Send

~

I -- -
.MOS TECHNQLQ~

Please ship me_ _ KIM-1 Systems at a cost of $245.00 per system plus $4.50 for
shipping, ~::::~:~i:::I is::~::~:e~~ -~ ~~:. ~:::a0::~::r:;i::::a:::s~% sales tax. Add $20.00 per system for shipping and handling of international orders.)

I I

:::_ec_k I o-r-mo-ne-y-or-de-ris-e-ncl-os-ed_fo_r $- - - - - -- - - -

....;;o;·;. · ,;.· · ·.;· · · ,;.· .. 1

KIM-1, _950 Rittenhouse Rd.

Address

I

;o~

CIRCLE NUMBER 33

E L ECTRON IC D ES IGN 7, March 29, 1976

67

Displays don't trouble 8-bit µPs. The µPs
easily provide information for displays as diverse as
simple digital types and data -demanding video term inals.

The data-handling capabilitie::; of 8-bit microprocessors are l>oth versatile and flexible enough to interface with displays that run the gamut from simple seven-segment digital types to complex CRT terminals.
A seven-segment digital display requires only infrequent updating, and when it is updated, very little information actually transfers to the display. A video-display terminal must be updatedor refreshed-very frequently (unless a storage tube is used), and that entails a large amount of data.
Data can be transferred from buffer memory to a <lisp.Jay by various methods. The simplest is a software~controlled tram;fer, which uses minimal peripheral-interface hardware. However, the software approach may turn out to be the slowest one when performed on the usual macroprogram level. Higher data rates can be obtained through microprogramming.
A completely hardwired direct-memory-access (DMA) approach achieves the highest throughputs. A microprocessor like the IMP-8 (Fig. 1) allows these and other data-transfer methods.
Treat the display as a standard peripheral device
When you use the 8-bit microprocessor,i.2 the display should be treated as a standard peripheral unit that attaches to the µP's bus in the same way that memory does. The IMP-8 instruction set contains no instructions specifically intended for peripheral operations. All peripheral transactions with the CPU are performed by standard memory-reference instructions, like Load Accumulator from memory and Store Accumulator in memory.
Two basic software-control meihod8-loop and in-line-may be employed on the macroprogram level.
The loop method executes a sequence of instructions over and over again (Fig. 2). This method
Roger Thompson, Microprocessor Engineer, Nation al Sem icondu ctor, 2900 Sem ico nd uctor Dr., Santa Clara, CA 95051.
68

ADDRESS BI TS l 0 -15)

OUTP UT DATA BITS
(0-7)

IN PUT DATA BITS
(0-7 )

HIGH ORDE R PROGRAM COUNTER l B- 151

DATA OUT BUFFER

~Bli5lel

----~~u~
A-BUS (B) 1

I .--------.

---1

I
I I
I
I I

CONDITIONAL

JU MP ll6 l MULTIPLE XER

~____,- TO PERIPHERAL UNITS (HALT FL AG IS I OF 16 CONTROL

FLAGS)

L----======'.___J CONTROL FLAGS ll6 l

FROM PERIPHERAL UNITS (START CONDITION IS I OF 16

CONDITIONS l

1. The IMP-8 , an 8 -bit mi croprogrammable µ P, employs two 4-bit RALU s (register and arithmet ic logi c un its) and one CROM (control read -on ly memory). The µP' s instruction set can be changed by modifying the existing CROM or by adding ext ra CROMs in parallel.

has the advantage that only a few words of code are needed to transfer a large block of data from memory to the peripheral. However, to keep track of the buffer word being processed, the pointers for the last-in, first-out stack must be incremented and tested continually. As a result, the actual rate of transmission is relatively slow.
In Fig. 2, BUFl represents the starting address of the first buffer. AC3, the t hird accumu lator, functions as the index register and increments once for each data word transferred. When AC3 becomes equal to zero, the loop will be terminated and the transfer of a second buffer can begin. For each pass through the loop, four machine instructions must be executed, requiring 44 machine cycles at 1.4 p. s (minim um) per cycle. Hence, one 8-bit wm·d can be transferred every 61.6 µs .
When only a few data words need be trans-
EL ECT RONI C D ES IGN 7. Ma rch 29 . 1976

ferred to a p~rip.1 .)ra !, the data rate can be increased about 50 percent by using the in-line method (Fig. 3). This method eliminates the control loop and uses instead a separate Load and Store-instruction pair.
In Fig. 3, BUFl is again the starting address an~ AC3 serves as the base index register. The short program increments the displacement value for each Load instruction. The method requires only the execution of two machine instructions for each data transfer, and these two instructions

tkal to the structures of other members of the IMP family." Each microinstruction specifies the exact function of the ALU and any external logic dur,ing that microcycle.
For example, ADD, AC3,, AC2 CIN
specifies an Add operation. The A-bus operand is AC3, and the B-bus operand is undefinedand consequently is interpreted as all zeros. CIN indicates that the result will be incremented. In this example AC2 indicates that the final result

START
INITIALIZE INDE X REGISTER

BUFl= X'l5¢ BUF2= X'25¢

;Start First Buffer ;Start Second Buffer

LOAD AC¢ FROM MEMORY USING
INDEX REGISTER
STORE AC fi{
INTO PER IPHERAL REG I STER
~ 'I
4

LI 3 ,D(BUFl) LDP 2 ,BUFl Loop: LD ¢ ,( 3) ST@ ·PERIF
AISZ 3,1 JMP ..-Loop LI 3 ,D(BUF2) LDP 2 ,BUF2 I
And so on ....
PERIF: .DWORD X'8D¢¢

Load Index Reg Load Page Load Data Indexed Store Indirect IN PERIF INCR and Test Index
Load Second Index Load Second Page

DONE
2 . The roop method uses only a few words of machine code to transfer an 8-bit word from memory to a pe· ripheral display. However, each transfer takes a lengthy

62 µ,s since stack pointers in the RALUs must be con· tinually tested and incremented. A speed-enhancing microprogrammed approach uses the same flow chart .

require only 26 machine cycles at 1.4 µ,s per cycle. Hence one 8-bit word can be transferred every 36 ,µ,s. However, the in-line method requires more memory to store the control program than does the loop method.
Microprogramming speeds data transfers
Other techniques for data transfer deal directly with the microprogram that controls the execution of each machine instruction. With the IMP8 µP, you can add or delete portions of the microprogram to .achieve an altered instruction set.
But microprogramming lengthens development time and costs, and it can entail additional CROMs (control and read-only memories). In general, this approach becomes economical only for high-volume applications.
IMP-8 microprogramming structures are iden-
ELECTRONIC DESIGN 7, March 29, 1976

(after incrementing) will be stored in that accumulator.
Several microinstructions are sequenced together to form a general subroutine. Each subroutine is executed as a response to a fetched and decoded macroinstruction from memory.
A microprogram-loop method like that discussed on the macropr-ogram level offers several advantages. First, the four-machine-instruction loop is rep·laced by a single machine instruction. And since aH data are transferred within the execution of a single machine instruction, the over-all data rate can be reduced dramatically.
The example in Fig. 4 requires only 9.2 machine cycles per pass through the loop. Since each machine cycle requires only 1.4 ,µ,s, each word transmitted takes just 12.9 µ,s. That's about 1/ 5 the time needed by the macroprogrammed loop.
The in-line method, when applied on the micro-
69

BUFl = X1 15¢

LI
LDP
START:
LD
ST@ LD ST@
LD
ST@

3 ,D(BUFl) 2 ,BUFl
¢,( 3) ; LOAD FIRST WORD PERIF ;?END TO PERIPHERAL ¢,1(3) PI:RIF ;SEND SECOND WORD
¢ ,2( 3) PERIF ;SEND THIRD WORD

AND SO ON .····

PERIF:.DWORD X1 8D¢¢

3. The in-line method increases the data rate of the loop method by about 50 percent when only a few words need be transferred. The routine reads a memory location's data into accumulator zero and then outputs that data to the peripheral. It then reads the next memory location ano transfer~ its data to the same· pe· ripheral. The routine continues to do so for each pair of Load and Store instructions.
program level, doesn't increase speed much over the microprogrammed-loop approach. Only two machine cycles can be saved per word transmitted. Everything else in the example remains the same. Thus, the transmission rate reduces to one word every 10 µs.
Because the total microprogram storage area is rather limited for the IMP-8, the in-line method should be employed only for very limited data transfers, even though .a comparison between this method and the macroprogram in-line version shows a 3-to-1 speed advantage. It requires only one machine instruction, as opposed to two for each buffer-word transferred.
Hardware-controlled data transfers
In the clock-hold DMA method-a hardware implementation-the requesting peripheral must generate a clock-hold request whenever it requires data (Fig. 5). The request temporarily stops the CPU clocks for a maximum of 10 µs. During this period, the CPU address buffers are disabled, allowing the requesting peripheral to take control of the address bus.
Data rates are limited to the cycle rate of the memory. For example, with a memory having 1-µs access, up to 10 words of data could be transferred during a 10-µs clock-hold period.
Since no software control is needed, the peripheral's request can be serviced in less than 1 machine cycle, or 1.4 µ,s. However only a limited
70

number of data words per request can be transferred; the clocks can be held only for a short period of time each machine cycle.
An interrupt-controlled DMA doesn't rely on a stopping of clocks. Instead, the peripheral requiring data requests a CPU interrupt.
The interrupt must be serviced under program control. First the DMA interrupt-service routine executes a Halt instruction, which sets the CPU Halt flag. This flag and its comp·lement then are used as the appropriate address-buffer enable/ disable signals. As was the case with the clockholcl method, data can be transferred at the cycle rate of the memory once the requesting peripheral obtains control of the address bus.
When data exchange has terminated, the requesting peripheral must raise the Start jumpcondition input to the CPU. This in turn resets the Halt flag that established the originail setting of the CPU address buffers. Once the Halt flag has been lowered, the Start input can be lowered, too. This returns control to the machine instruction that follows the Halt instruction in the interrupt-service routine.
Although the method doesn't .handle data any faster than the clock-hold method, it can trans· fer as many words as required. However, an interrupt-latency time exists between the actual interrupt request and the time the first word is transferred. For the application described, the latency time is about 75 .µs, corresponding to the time needed by the µP to prepare for its execution of the Halt instruction.
Organize a two-port memory
In all of the examples described, the buffer memory was presumed to be part of the mainsystem memory. But since data are all that are being transferred, there is no reason for the buffer memory to be organized the same way as the instruction memory. In fact, if the buffer is organized as a two-port memo·ry, high data rates can be sustained for any length of time without the need for a µP interrupt. This, in turn, would eliminate the interrupt latency time, and allow transfer of data within one machine cycle or 1.4 µ,s on the standard IMP-8.
One port performs read-only operations, and is controlled directly by the peripheral. The second port, a write-only, is connected to the main µP I/ 0 bus.
The µP generates data and stores it in the buffer memory, from which the peripheral takes data. However, the buffer memory does not ackno.wledge the transfer to the IMP-8 µP. Aftert each write operation, the CPU must check the buffer to determine if it is in a DMA mode. Only when the buffer completes a data transfer can the µP write in new data.
ELECTRONIC DESIGN 7, March 29 , 1976

*

MEMORY ADDRESS REGISTER(MAR) CONTAINS PERIPHERAL

*

PAGE ADDRESS.

*

MEMORY DATA REGISTER(MDR) CONTAINS PERIPHERAL

*

BYTE ADDRESS.

*

ACCUM 3 CONTAINS BUFFER PAGE ADDRESS.

*

ACCUM 2 CONTAINS BUFFER BYTE ADDRESS.

*

*
LOOP PFLG,HI ,MAR,,¢ ¢

* SEND HIGH ORDER PERIF ADDRESS

PFLG.LO,MDR, ,¢ ¢

* SEND LOW ORDER PERIF ADDRESS

PFLG,WRITE,AC¢,,¢ ¢

* WRITE DATA IN AC¢ TO PERIF

ADD,AC3, ,AC3

CIN * INCR AC3

B,NREQ¢

CONTINUE,FETCH *TEST, IF BUFFER DONE

* FETCH NEXT MACHINE

'" INSTRUCTION

CONTINUE

PFLG.HI,AC2,,¢ ¢

* SEND BUFFER PAGE ADDRESS

PFLG.READ,AC3,,AC¢ DATAIN * SEND BUFFER BYTE ADDRESS, THEN

-J: READ NEXT WORD IN BUFFER

* SAVE IN AC¢ FOR NEXT TRANSMISSION

B

WOP * REPEAT IDOP

4. A microprogram-control version of the loop method increases data rates by a factor of five. The listing, which shows the source code to a microassembler, implements

the flow chart shown in Fig. 2. The first several lines essentially are comments that identify the locations of different pieces of information .

PERIPHERAL OMA REQUEST LOGIC
PER I- I OMA PHERAL : ADDRESS I BUFFERS PERIPHERAL OMA ADDRESS COUNTER

CLOCK HOLD REQUEST
DISABLE CPU ADDRESSES
DISABLE OMA ADDRESSES
CLOCK DATA TRANSFER
MAX COUNT ACKNOWLEDGE
OMA TRANSFER RATE CONTROLLER

11

-----~I ~1- - - - - -
1 I

I I

r-------111....- - -...

11

_ _ __1,1I

I

1 I

_____ru--i µ-u-i_

--------411 1

n. ~----

11

5. A completely hardwired transfer technique-clockhold OMA-can service a peripheral 's data request in
less than one machine cycle, or 1.4 µ,s . But only a limit-

ed number of words can be transferred, because the clocks can be held only for a short period during each machine cycle.

When the peripheral requests data from the buffer, it must wait only until the completion of any previous µP write operation. Since this is always less than one machine cycle, the peripheral requesting data always gains access in less than one machine cycle.
The examples given in this article are by no means the only methods of transferring data from memory to peripherals. In fact, it may be possible to combine these methods to satisfy different application requirements. Also, the examples cover only the case of transferring blocks of data from memory to peripherals. The same concepts hold true, with minor modification, for
ELECTRON IC D ESIGN 7, March 29, 1976

transferring to the microprocessor's memory data from the peripheral device.
Moreover, the same methods can be us ed with the IMP-16, a 16-bit version of the IMP-8. In all cases, the rate of transmission will be comparable and the hardware required will be similar. The only significant difference is that 16-bit data words will be transferred where 8-bit words were before. ··
References 1. IMP-8 Applications Manual, Publication #4200032,
National Semiconductor, Santa Clara, CA 95051. 2. I MP-8 Prograrn11ning Manual, Publication #4200031,
ibid. 3. IMP Microprogramming Manual, Publication
#4200062, ibid.
71

CONTINENTAL CONNECTOR .·. for economy in connectors

SEND FOR FREE E600 TECHNICAL BOOKLET!
E-conn printed circuit board connectors provide reliable performance at lower cost - flame retardant glass fiber filled Diallyl Phthalate molding material and phosphor bronze contacts with gold plate over nickel. This group also features patented "Bellowform" contacts with choice of solder lugs, dip solder terminals or .025" and .045" square solderless-wrap terminations. Write or phone Continental Connector Corporation for your free booklet: 34-63 56th Street, Woodside, N.Y. 11377; (212) 899-4422.

For the Sales Representative Nearest You, See Our Listings in EEM and Gold Book Directories
CONTINENTAL~ CONNECTORS
CONTINENTAL CONNECTOR CORPORATION· WOODSIDE, NEW YORK 11377

CIRCLE NUMBER 34.

72

CIRCLE NUMBER 35 ·

TEOHNOLOGY

Unite µP hardware and software the

easy way. Design a universal test system that

.

checks, debugs or troubleshoots-from breadboard to field.

When you near the end of a µP-based design and face the problem of joining the nearly completed hardware to the almost finished software, let a universal test system officiate at the final coupling.
Such a test system can be very useful. First, it allows you to communicate with the µP system through a keyboard. Second, the program can be loaded into a RAM memory from tape generated by either time-sharing or a proprietary development system like Motorola's Exorcisor. Then the µP system can be operated from the prog_ram as stored in the RAM. Third, selected port10ns of the program can be exercised, and the program modified to perform special tests or system-hardware adjustments. The RAM memory can be tested to ensure that it is operating properly.
A particular advantage in programs with a short turn-around time is that system development and software debugging can proceed on hardware in the breadboard or prototype stage.
Finally, as the system nears completion, it can be operated entirely on its own, but with the test option available in case problems develop.
The test system can still be used for production units even after the µ,P product is finished. And when the products are out in the field the test system can serve as a troubleshooting aid, for both hardware and software.
No need to change standard procedure
In developing a µ,P system you usually follow a standard sequence of steps : 1. The system requirements are written down in statement form. 2. Algorithms are developed from these statements. 3. Rough code is written and assembled to implement the algorithms. 4. The code is simulated and refined on either a time-sharing system or on a proprietary development system like the Exorcisor or Intellec.
Eventually, you must fit the refined program into the hardware system. This ultimate mar-
Jim Barnes, Senior Project Engineer, and Bert Bergquist, Design Engineer, Motorola Semiconductor Products, 5005 E. McDowell Rd., Phoenix, AZ 85008.
74

HOST MICROPROCESSOR INTERFACE

BIT - RATE GEN

- D A T A BUS

TERMINAL INTERFACE

1. A universal test system consists of a humber of LSI and MSI packages . The ROM holds the test program, the RAM acts as a scratchpad , and the ACIA interfaces the terminal with the test system.
riage may not occur until after the system is prototyped. What makes the test system so effective with small ,µP systems is that it interfaces with existing hardware without significant modification to that hardware.
Hardware for the test system consists of three LSI packages, four conventional IC packages, an interface connector to the terminal and additional interface connections to the data, address and control buses of the host µP (Fig. 1).
The LSI packages-all components of the M6800 µP family-include the Minibug II firmware ROM (this is the same ROM supplied with Motorola's Evaluation Module II), the M6810 RAM as a scratchpad and the M6850 asynchronous communications interface adapter (ACIA) for connection to the terminal.
MSI packages include the MC14411 bit-rate generator, the MC14025 gate package for ACIA address decoding and the MC1489/ MC1488 pair, which provides the RS232 interface. If you use a TTY terni.~nal requiring a 20-mA current loop, then a 4N33 optocoupler can act .as the interface.
The ROM provides the program that recognizes both requests to perform standard operations and the routines that actually perform
ELECTRONIC DESIGN 7, March 29, 1976

fiP VECTORS MI NIBUG PROGRAM USER'S PROGRA M
MINIBUG RAM
Ml NI BUG ACI A

PRIMARY ADORESS
EFFF, EFF8, EIFF,
EOOO.
cooo.
A07F, AOOO.
8007, 8004,

ALIAS ADDRESS
FFFF FFF8 FIFF
FOOO
0000
8075 8000
9007 9004

[ usrn·s4

0000,

1000

2. The memory map shows wired addresses and those used durin g syste m sta rt -u p.

:::::3 D OE

Al3

,

0

'b Vee

) :·::

D

OE

Al3~
' Vee

®

3 . Generation of syst em-enable signal : in the TEST mode, firmware decodes C to generate an enable signal
(a) . Without TEST, C or E is decoded (b). Response is t o
CXXX 9r FXXX, depend ing on whether A, 3 or Vee is con nected.

t hem. The RAM-in addition to providing dedicated storage areas for stack, target, interrupt and data-enclosing vectors-also contains a small area t hat can hold limited test routines. Finally, t he ACIA provides the .serial-to-parallel interface to the terminal.
Connecti,:m of the test system is complicated by t he µP-contro lled start-up sequence. The µ.P's first action is to put all address lines, except Ao, at the HIGH level (hexadecimal address FFFE) and then look for the 'high-order byte of the program's starting address. Next, the µP puts A0 H IGH (hex FFFF) and looks for the low-order starting-address byte.
When a program like the Minibug II is used, ,µ,P action must direct a vector to th~ start of the Minibug II ROM; when the operating system is used alone the same action must point to the start of the system ROM. Similar requirements exist for the interrupt vectors located at FFF8 through FFFD.

Equalizing t he addresses
The Minibug ROM is wired to respond to address EXXX, but it must also respond to FXXX at system start-up. To see how this can be accom-
i::LECTRONIC DES IGN 7, March 29, 1976

plished, you must interpret these locations in

terms of the actual address lines. Hex E and F

are equal to binary 1110 and 1111, respectively.

The corresponding address line configurations
are A ,;;, A H, A ,a, A12 and A ,s, A ,", A 13, A u respec-
tively.

To ma.ke addresses E and F react equally, you

ne!'!d only make A ,, an X, or a Don't Care. Then

the Minibug II ROM-though wired as EXXX-

will respond to FXXX.

As shown in Fig. 2, the Minibug II program

also reserves AXXX for its RAM and 8XXX for

its ACIA. With A, 2 as a Don't Care, the BXXX and 9XXX are unavailable without additional

decoding. Since the low-order addresses usually

are reserved for peripherals and program RAMs,

the CXXX (or DXXX) 2-k byte area is only

recommended for programs in small systems ;

more than 2-k bytes of program call for addi-

tional hardware decoding.

When you compare hex F (binary 1111) and

hex C (binary 1100), and realize that you have

already made A,2 a Don't Care, you see that F and C differ only in A, 3. Take advantage of this

situation: Hook-up a single-pole, double-throw

switch to determine whether the system is in the

Minibug II or system-ROM program. Figure 3

shows how to generate the system-enable signal,

E. The ·signal responds to CXXX when A, 3 is connected and to either CXXX or FXXX when

Vcc is connected.

In operation, the system calls those functions

that accomplish the desired end. These functions

include:

.

· Read a memory location to a printer.

1· Write into any memory location from an

external keyboard.

· Write into memory from tape.

· Print a designated section of memory on

either printer or tape (with computed checksum).

· Vector to a target program.

· Memory test (five patterns and a walking-

bit test).

· Punch and load binary tape.

The memory-test function allows exhaustive

testing of any block of memory the designer may

designate by use of the M function. The tests are

as follows:

· A Walki11g address.

· B Write FF into all locations and verify.

· C Write AA into all locations and verify.

· D Write 55 into all locations and verify.

· E Write 00 into all locations and verify.

· W Write a single walking bit through the

entire memory.

As each test is completed, the corresponding

letter is typed-if a test fails, the user knows

immediately which one.

The function, "Punch binary tape," allows

punching the exact contents of memory on tape

75

Table 1. Memory examine-and-change sequences

ENTER (Command)
M
xx xx
(4 Hex digit memory loc.)
xx
(2 Hex digit of new data.)
C.R. or L.F. or i

RESPONSE Space Space XX (2 Hex digit of memory contents.)
1) C.R. stores data and responds with*
2) L. F. stores data, increments ad· dress and opens that location.
3) i stores data, decrements ad-
dress and opens that location.

4. How test system connects to host µP system. Little hardware change usually is needed to interconnect the two systems. A TTY terminal can be used .

Table 2. Test system response and command

ENTER (Command)
G
R
w
y
z

RESPONSE Space
Space

ENTER
xx xx
(4 Hex digit users starting address)

RESPONSE
Goes to user's program and executes instruction sequence.

DISPLAY REGISTERS
Prints register contents as follows:
xxcondition code AxCxCB ACxxCA INxDxExXxP COxUxNxTxER SxTxAxCxK

MEMORY TEST FUNCTION ABC DEW, carriage returns, prints*.

PUNCH BINARY TAPE Tape is punched, carriage returns and prints*.

READ BINARY TAPE Memory is read to printer, carriage returns, prints*.

-no ASCII II conversion is made, as is when talking with a printer. A tape header is generated that includes the word count and starting address. Record length is 256 words. If the record is longer, another header is inserted after each 256-word sector.
The "Read binary tape" function is exactly the inverse of the punch binary tape function-the record is written into memory at the starting address contained in the tape header.
Note that, with the test system, the memoryexamine-and-change sequence should be learned first, because this sequence sets up portions of other commands (Table 1).
With the test system and a terminal both properly connected to your system (Fig. 4), and with the power on, a press of the system reset or restart button causes the terminal to respond with a carriage return, line feed and a printed asterisk. The system is now ready to accept commands from the terminal.
76

To load tape into memory, first load a formatted tape into the terminal and set the tape reader to Auto. Then just enter the command "L" following the asterisk, and the tape is loaded. To print out the memory contents or punch a formatted tape, first enter the high and low-order starting-print address into memory locations A002 and A003. Then enter into locations A004 and A005 the high and low-order END print address. After the asterisk appears, enter the command "P." The response is p1rintout or recording of the formatted data.
To use the program-interrupt sequences, enter the assigned addresses into the test system as follow.s: at memory locations AOOl and A002, the high and low-order hardware-interrupt vector; at A006 and A007, the nonmaskable interrupt; and at AOOC and AOOD, the software-interrupt vector.
The various commands associated with the user's program are given in Table IL ··
CIRCLE NUMBER 36 ·

Darlingtons
that last.

Whether you use Darlingtons or discretes, without high-temperature stability, you're dead. Failure may be a boon to the aftermarket, but for OEM's it can start something big ... and bad.
Stability testing of IR Darlingtons shows a remarkable 210 microamps leakage after operating 1000 hours at 400 Volts V cn and 150 °C! We don't think anyone can top it with present technology.
It's due to our hard-glass passivation techniques, plus 28 years' experience building high reliability power semiconductor devices.

formance you need for switching power supplies. Like a rise/storage/fall time total that's typically 50% below maximum rating, guaranteed minimum gains, plus lower sats and a wide SOA.
New 900V Darlington Series
While you're getting data, ask about our new super-voltage, 500 to 900Volt V CEO(sus)devices, and our many other high gain high-voltage series for 5KHz applications.
And if you're thinking of paralleling, ask for our "Paralleling Power Transistors" paper.

New 20KHz Series
Our three new series of fast-switching Darlingtons (using an internal speed-up diode) give you this superb stability, plus the great per-

Series
IR6251 IR6000 IR6060

le Peak
15A 20A 25A

Total max tr/ts/tf
3.75µ5 3.90µ5 3.90µ5

YcE0(5U5J
350-450V 300-400V 300-400V

3 New Series for 20KHzSwitchers.

It's full of valuable information that can save you a lot of time and money.
Above all, think of our device stability. For more peace of mind ... at no extra cost.

InternationalRectifier II\iRI

the innovative power people

233 Kansas St. , El Segundo, CA 90245, (213) 678-6281

CIRCLE NUMBER 37

78

E LECT RON IC D ESIGN 7. Marc h 29, 1976

Fairchild's FB Formulator: It gets you from µ.,p design to hands-on prototype in half the time.

The Formulator is a powerful new microprocessor development tool that offers you all the design assistance you'll need to develop a microprocessorbased system or product. It saves time by:
1. Eliminating the need for an external system breadboard.
2. Putting your design energy where you need it: On the nonmicroprocessor circuits and on the operating features of your total product.
3. Providing real-time program execution. The system uses actual F8 1/0 components to provide 1/0 to the system, ensuring an exact reproduction of F8 waveforms and circuit levels.
4. Enabling you to edit, assemble
ELECTRONIC D ES IGN 7, March 29, 1976

and debug fast and efficiently.
5. Keeping all the system software resident in the machine while developing your program. No loading and reloading of system software.
6. Providing an intelligent front panel which makes debugging effortless.
7. Letting you examine and alter storage, set hardware breakpoints and single-step the central processor.
8. Providing self-test at the push of a button.
The Formulator can be interfaced with either an HP2644 terminal or an ASR33. Fairchild offers a fully integrated software package including an operating
CIRCLE NUMBER 38

system complete with monitor, text editor, assembler and debug package. The Formulator was designed by systems people with reliability and maintainability as a design criteria. Each Formulator is burned in for 120 hours at 120°F prior to shipment. The Formulator can be delivered immediatelylease or rental plans are available. Write for more information to: Fairchild Microsystems Division of Fairchild Camera & Instrument Corporation, 1725 Technology Drive, San Jose, California 95110. Phone (408) 998-0123
FAIRCHILO
MICRO SYSTEMS
79

TECHNOLOGY

Eliminate static damage to circuits
by tracing its causes and reducing the voltage levels. Conductive floors and clothing help, but are not enough.

Static discharges can damage many solid-state devices, but you can prevent this by using an energy-storage model to help minimize the causes of static buildup. Many of the potentially dangerous electrostatic voltage levels are generated by operator movement or assembly-line movement.
Relatively low static-voltage levels can damage not only MOS devices, which are commonly recognized to be static-sensitive, but also junction field-effect transistors, some bipolar devices, diodes, thick-film resistors and other small junction devices. The potential for damage is especially severe in the low-relative-humidity environments usually found in assembly and design areas.
Fig. 1 shows typical static-discharge damage sustained by a 2N3112 JFET. In some circuits the JFET will still function and appear normal, even though localized heating from the static discharge has melted a thin elliptical section and lowered the reverse breakdown voltage to below normal.

discharged through a 1-kn resistor. From the discharge waveform, we can determine the peak current, Ip, and the discharge time constant, T('· The value of IP is then compared with the peak current Io, which is the value of the body current
if RH = 0 and CH = 270 pF. R,, and CH are then calculated and found to be: RH = 87 to 190 n and
CH = 132 to 190 pF, which compares favorably with earlier results obtained under discharge test conditions .'· 15 So, for the rest of this discussion,
the values Rn = 100 n and Cn = 218 pF will be
used.
Determine device sensitivity
Let's see what happens to a 2N4118A JFET if we use these three test methods to judge static discharge damage (Fig. 3) :

Use an energy-storage model
To study the effects of operator-generated static-energy discharge on semiconductor devices, use an energy-storage model of the body (Fig. 2a). The body acts as one plate of a capacitor, CH, which is in series with the skin and body resistance, R,, . The other plate of the capacitor is formed by the ground.
Published values for C,, range from 100 · to 10,000 pF and from 0 to 18 kn for R,.,, depending upon the measuring method selected. 1-1 6 To arrive at realistic values for use in this article, the measurement circuit of Fig. 2b was used to compute RH and CH from ·charge and discharge waveforms observed on an oscilloscope.
The test subject was connected to a mercury relay through a wrist strap that had a surface area of 40 sq. cm. First, the subject was charged to a de potential between 200 and 2000 V, then

Whitson J. Kirk Jr., Lane S. Carter and Max L. Waddell, Staff Engineers, Electronic Products Dept., Bendix Corp., P.O. Box 1159, Kansas City, MO 64141.
80

1. Static damage to a JFET can be caused by voltage discharges into the gate without necessarily destroying the JFET. However, the JFET fails more readily if stressed near its voltage limit.
ELECTRONIC DESIGN 7, March 29, 1976

1. A human-body model charged with a de power source.
2. A human body charged with static voltage generated by movement.
3. A human body charged with a de power source.
In each test, CH was charged to a known voltage and then discharged through the gate-source junction of the JFET. A change in the junction reverse-breakdown voltage at a junction current

breakdown voltage, with no significant change in transconductance or pfoch-off voltage. These devices would perform normally for a time in many applications. However, the effects in Fig. 1 resemble the melt transition that results from the second breakdown of a pn junction." And increased current density in the melt region can reduce operating life and power-dissipation capability.1 '·19
· The resistance .in series with the JFET gate

Table 1. Observed effects of JFET test

Test Conditions·

Device-Failure Voltage Levels2 70 85 100 120 140 160 190 230 270 320 380

Human-Body Electric Model Direct-Current Charge Rn = 0, CH = 97 RH = 0, CR = 218 RH = 0, CH = 425 RH = 100, CR = 218
Actual Human Body Movement-Generated Charge Direct-Current Charge

D

D

D

CCD

cc

c

c c D

D CCCD CODD CCDD cc

c D

D

DD c

c

Notes:
1. RH values in ohms, CH values in picofarads.
2. Each JFET receives one discharge pulse at each test voltage until failure occurs. The letter C indicates catastrophic failure when the reverse breakdown voltage drops to less than 3 V. The letter D indicates degradation when the 5-µA gate-source reverse breakdown voltage decreases by 50%.

of 5 µA provides a sensitive indicator of degradation. The results of this experiment are summarized in Table 1. Degradation did not vary appreciably with different discharge sources.
Other results from this experiment include these:
· The discharge levels at which the failure occurred were lower with reverse-breakdown polarity (100 to 380 V) than with forward-conduction polarity (600 to 765 V) on the gate-source junction.
· The capacitance value or energy level influenced, to some extent, the voltage required to degrade the transistor. CMOS circuits with diode protection were also found to be energy-sensitive. Unprotected MOS proved to be voltage-sensitive rather than energy-sensitive.
· Repeated discharge pulses at voltages below the degradation level didn't significantly degrade the device. This indicates that progressive degradation from repeated pulses is minimal. The mean degradation voltage for a 15-sample group that received a single pulse at each voltage was 282 V. Another group of five devices was given 10 pulses at each voltage; these ended up with a mean of 230 V. There was no statistical difference between the two groups.
· Half of the JFETs showed a decrease in
ELECTRONIC DESIGN 7_ March 29, 1976

r-------,

I

I

I

RH

I

TH I
I

_ c - jI

fa\

I

I \J

I

1-fJMAN-BOOY I

I _-_ = _ _MO_DE_ L _JI

'-----<>--~

M~~~~y~

·

-

'""'"'f ---: -rk
PROBE

0"''""""" I

RH · [Uo - Ip) /lp]!I03)

CH ·TC/( RH+ 103)

t lo Ip !

1---rc---J

2. A model of the human body starts the analysis of how voltages build up (a). By measuring the rise and decay times we can calculate the time constant and thus the values of RH and CH (b).
81

-IM
..----'V'.1V--~-olo-~-G-AT-E~+.~

IOk
DRAIN
JUNCTION FIELD-EFFECT TRANSISTOR
SOURCE

RH
Cti
1-

RH · BODY RESISTANCE
CH ·DISCRETE CAPACITOR OR HUMAN BODY

3. The charge-discharge model for the human body indi· cates how energy is stored from a de source and then discharged through the small-signal device under test.

limits the current arising from discharging voltages, thereby providing some protection to JFET and CMOS devices. Normal body resistance doesn't sufficiently isolate the device. Series resistances well above 1 Mn are required for protection against voltages as high as 4 kV.
In another study, several bipolar transistors, some diodes and some FETs were tested with the circuit of Fig. 3. The results are tabulated in Table 2. Initial pulses for MOS devices were 16 V; for all other devices, they were 70 V. If the pulse resulted in no change in the reverse breakdown voltage, the pulse voltage was increased by 20 % and the test repeated; the maximum vo.Jtage applied was 3 kV. Although FETs proved to be the most sensitive to static discharge, some degradation of the other devices was found.
Measure operator-generated voltages
Now that we've determined that many semiconductors can be affected by static discharge, let's see how we can measure voltages generated by subjects in a typical work environment. The system described in Fig. 4a can measure and record the voltages, and it can respond in 12 µ,s. Critical to the circuit's operation is the maintenance of the capacitively coupled probe at a fixed,

calibrated distance from the conductive disc connected to the operator. 2·> A typical voltage output generated by the subject intermittently gliding on an insulated chair and walking across a conductive floor is shown in Fig. 4b.
The floor was of conductive vinyl tile, which has a resistance of 0.95 Mfl. 21 The chair was insulated with rubber rollers, and the subject was wearing composition-soled street shoes. The relative humidity was 4 %. Under these conditions, spikes of 700 V were generated ; these can degrade small-junction devices. Although portable static meters and electrostatic voltmeters can measure de static voltages, they cannot detect rapid transients. 22
After the subject had been monitored for several conditions, the results were summarized (Table 3) and some conclusions drawn:
· With the exceptions noted in the table, peak generated voltages were observed at points where the feet of the subject partly or totally lost contact with the ground plane. This is typical when a reduction in capacitance increases triboelectric voltage.
· Conductive-soled shoes or conductive shoe covers limit voltage generation on a conductive floor to 50 V or so, as long as the shoes remain in contact with the conductive surface.
· When the relative humidity is 45 % , a subject's street clothing does not provide a conductive path between the skin and the conductive seat of a chair. (Typical resistance through street clothing was found to be about 10 Gn).
· Neither conductive shoes on an insulated floor nor insulated street shoes on a conductive floor provide static protection.
The time it takes for a movement-generated charge to dissipate is also important. The graph in Fig. 5 shows how voltage dissipates from a 500-V starting level for a variety of environmental conditions. With conductive shoes, on a conductive floor, the charge on a subject can dissipate in less than 1 ms, which means there

COPPER DISC 0 .0 7 6 m

10,000 . I PROBE (STATIC-HEAD ACCESSORY FOR El£CTROMETERl

El£CTROMETER
( >I014 -ohm INPUT
RESISTANCE)

OSCILLOSCOPE

ROLLING ACROSS A.OOR

SEATED ON INSULATED CHAIR

"'

I· I ·I ·I· I

WALKING

I

~ eoo..--~.....--r--.--.--.---.~.--..---.

0

> 6001--t --ft--+-tt-tr-+-r+--1-t---c+--t
_j

.gwz....

4001--+-r.vf-'Hi'Mll.-fl~,......,,.,...PV-'llol--I
2001--+lllt-ll-.........-H'.........- +-ff+ll*--l+--+--t

~ o.__..._.....__...__.__,___,___,_..._+-..__.

0

10

20

30

40

TIME , SECONDS

FEET RAISED FROM FLOOR

T

DIRECT-CURRENT CALIBRATION OBTAINED BY ADJUSTING

CAPACITIVE COUPLING

4. To monitor the generated electrostatic voltage, a test set can be built with an electrometer amplifier (a). The

voltage peaks generated by the moving subject can be measured on an oscilloscope (b).

82

ELECTRONIC D ESIGN 7, M arch 29, 1976

is a good probability that any charges will dissipate before contact is made with a static-sensitive device. The three rates observed with leather street shoes on a conductive floor vary so markedly that this combination cannot be considered reliable. All other conditions studied have even slower discharge rates, though, which makes them even more dangerous.
As seen on the graph, an increase in relative humidity decreases the discharge time for composition-soled shoes on a conductive floor. Ho·wever, to ensure adequate protection, a relative hu-
midity much higher than 45 7o would be required,
but then the working conditions might become uncomfortable or undesirable for sensitive circuits.
The effect of subject-to-ground shunt resistance on the peak voltage generated is shown in Fig. 6. For the shoe and floor materials tested, any combination of conductive devices that always ensures a resistance of less than 10 Mn between body and ground provides good static protection for MOS devices and an R of less than 100 Mn for junction devices. Other materials, such as rubber-soled shoes or waxed floors, could produce higher peak voltages, which would then require lower shunt resistances.
Minimize the static hazard
By modifying facilities and process procedures, you can minimize the hazard of static-discharge damage to solid-state devices without requiring an operator to think about being grounded before handling components or assemblies. A wrist strap offers poor grounding protection, at best.
Minimum design requirements for a staticdischarge-protected facility include:
· A conductive floor with a resistance in the 25-to-300-kn range, tested in accordance with National Fire Protection Association codes. The 1-Mn upper limit in the codes is marginal; an upper limit of 300 kn indicates a more uniform distr.ibution of conductive p·ath and thus lowers peak voltages.
· Conductive shoes with a maximum resistance of 500 kn, tested under the same guidelines as the floor.
· Conductive chairs with a maximum resistance of 1 Mn between the seat and a metal plate under the chair. If a foot rest or rollers are provided, they also must be conductive. (Although the conductivity through an operator's clothing may be low, the presence of the grounded seat reduces voltage amplification when the feet of the operator are lifted from a grounding plane.)
· Conductive foot rests under the table. To validate reliability, at periodic intervals resistance measurements should be made on each operator at his work station. The operator-to-
ELECTRONIC DESIGN 7, March 29. 1976

Table 2. Typical device degradation threshold

Device
Diodes 1N459 1N916 Tl551 1N4151
Zener Diodes LVA356
Transistors 2N2222 2N2369A 2N2432A 2N2540 2N2907 2N3117 2N3570 2N4251 2N4872 2N5154
Junction Field-Effect Transistors
2N2608 2N3112 2N3971 2N4118A
Metal-OxideSemiconductor Transistors
GI MEM 520c (chip)
Complementary Metal-OxideSemiconductor Integrated Circuits
RCA CD4001
SiliconControlled Rectifiers
2N886A 2N3030

Thresh hold, 1 volts

Test Resu Its
Degradation criteria 2

> 3000 3000 450
> 3000

50 % drop in VH at
la = 5 µA

50 % drop in Va at
> 3000 I. = 5 µA

1000 460 620
1450 1200 1000
380 460 1200
>3000

50 % drop in V ,n·>C'no at
I,. = 5 µ,A

50% drop in v (RR>GSS at
lu = 5 µA

320 530 160 140
IG>5µ.A at
Vus = 22 V

58
> 0.5 µA input at
10 V or
> 10% decrease in
output voltage across 100-kO load 250
50% increase in lcoo

680 1000

Notes:
1. Reverse-breakdown polarity.
v. 2. Where is the reverse voltage, 1. the reverse
current, V1.. :ceo the collector/base breakdown voltage, 1, the base current, V1e· iGss the gate/source breakdown, IG the gate current, VGs the gate/source voltage and lcGo the gate leakage current.

ground resistance is voltage-dependent and cannot safely exceed the limiting protection resistance implied in Fig. 6. A system check like this accounts for the random distribution of conductive particles on both floor and shoes, and should be used to supplement standard floor and shoeresistance measurements. And don't forget conventional precautionary equipment, such as conductive tabletops, conductive foam packaging and soldering irons with grounded tips.
The spray cleaning of electronic assemblies with
83

Table 3. Typical generated voltages

Shoe/Chair Combination

Conductive Floor I"

Peak Voltage Generated 1 Conductive Floor 113

Insulated Floor'

Conductive-Soled Shoes Conductive Chair Insulated Chair
Leather-Soled Shoes Conductive Chair Insulated Chair
Composition-Soled Shoes (man-made) Conductive Chair Insulated Chair

20 340 1200 500" 500'·

100 500
370 900
1100'· 1100'·

700 600 800 1050'' 1550

Notes: 1. For an operator walking to chair, sitting down and lifting feet.
2. A conductive tile floor with 0.27-Mn resistance, relative humidity of 45%, R9 of 0.5 Mn from operator through conductive shoes and floor to ground, with 1 µA measuring current.
3. A conductive tile floor with 0.95-Mf! resistance, re lative humidity of 4% and R. of 11 Mf!. 4. Insulated vinyl tile floor and relative humidity of 4%. 5. Peak voltage observed during walking phase of operation.

OPERATOR POTENTIAL,
VOLTS
50

20

IO

20

30

40

Tl ME · SECONDS

5. Electrostatically generated voltages decay at a rate that depends upon the relative humidity and the mate·
solvent after soldering operations can also generate potentially dangerous electrostatic charges. "" The polarity a.nd magnitude of the charges is a. function of the resistivity of the solvent, the spray rate and the triboelectric voltages or contact potential of the solvent and assembly materials. Assemblies that get this precharge can be damaged if the gate of a JFET is accidentally grounded. The charge, however, must have the proper polarity to impose an excessive reversebreakdown potential on the gate.
To study the effects of various solvent systems, several solvents that produce positive and negative charges were used to neutralize the voltage on a printed-circuit board.
The PC laminate selected was epoxy glass (Type GH per MIL-P-13949), the spray pressure wa.s 234 kilopa.scals (34 psig), and the relative humidity wa.s 4 % . Table 4 shows some of the compositions studied, and the test results are plotted on the graph of Fig. 7. Mixing a low-resistivity solvent with the normal cleaning solvent results in .improved control of charge generation.
The upper limit on solvent volume resistivity

SHOE SOLE

--
~

COMPOSITION OR LEATHER
LEATHER

- 6 - COMPOSITION

~
--- --

LEATHER COMPOSITION COMPOSITION

--0-- CONDUCTIVE

LEGEND FLOOR
VINYL
CONDUCTIVE (0.27 MAI
CONDUCTIVE l0 .95 MO.) CONDUCTIVE (0.27 MO.) CONDUCTIVE lO 27 MO.) CONDUCTIVE tO 27 MO.) CONDUCTIVE

RELATIVE HUMIDITY
4 °/o 5 .,. 4·1. 45% 5·1. 45°/o

rials in the floor and clothing . Decay times can take several minutes to reach safe levels.
for adequate protection under the test conditions
was 50 kD.-m. Although ethanol was used in the
controlled experiments, other low-resistivity po-
lar solvents are equally suitable. · ·
References
1. Lenzlinger, Martin, "Gate Protection of MIS Devices," IEEE Transactions on Electron Devices, (Vol. ED-18, No. 4, April, 1971, pp. 249-257.
2. Morse, A.R., comment on paper by W.B. Kouwenhoven and W.R. Milnor, "Field Treatment of Electric Shock Cases I," A/EE Transactions on Power Appamtus and Systems Part Ill Vol. 76, No. 4, April, 1957, pp. 82-87.
3. Lee, Ralph H., "Electrical Safety in Industrial Plants," IEEE Spectrum, Vol. 8, No. 6, June, 1971, pp. 51-55.
4. "Using Electrically Operated Equipment Safely With the Monitored Cardiac Patient," Hewlett-Packard Co., Waltham, MA, March, 1970, pp. 22.
5. Molinski, A.E., "Effects of Electricity on the Human Body," Mining Congress Jounwl, Vol. 56, No. 7, July, 1970, pp. 64-68.
6. Friedlander, Gordon D., "Electricity in Hospitals : Elimination of Lethal Hazards," IEEE Spectrum, Vol. 8. No. 9, September, 1971, pp. 40-51.
7. Montesi, Louis J., "The Development of a Fixed-Gap Electrostatic Spark Discharge Apparatus for Characterizing Explosives," Proceedings of the Sfrth Symposinm on Electroexplosive Devices, San Francisco. July 8-10, 1969, The Franklin Institute Research Laboratories. Philadelphia. PA. pp. 2-8.1.

84

ELECTRONIC DESIGN 7. March 29. 1976

Table 4. Cleaning solvent mixtures

Solvent System
A
B
c

Component
trich loroethylene trichlorotrifluoroethane ethanol methanol
tetrach loroethylene 2-ethoxyethanol trichlorotrifluoroethane ethanol methanol
-
trich loroethylene ethanol (200-proof)

Compositions Studied Concentration , percent by volume

100.0 0.0 0.0 0.0
80.0 20 .0
0.0 0.0 0.0
59.6 } 40.4

90.0 6.5 3 .2 0.3
66.4 16.6 11.0
5.4 0.6
azeotrope

80.0 13.0
6.3 0.7
60.0 15.0 16.3
7.8 0 .9

72.5 17.9
8.6 1.0
53.6 13.4 21.5 10.3
1.2

50.0 32.5 15.7
1.8
40.0 10.0 32 .5 15.7
1.8

8. Petrick, John T., "Discharge of an Electrostatically Charged Human," Proceedings of the Sixth Symposium on Electroexplosive Devices , San Francisco, J uly 8-10, 1969, The Franklin I nstitute Research Laboratories, Philadelphia, PA, pp. 3-5.1.
9. Silsbee, Francis B., "Static Electricity," National Bureau of Standards Circular C438, June 10, 1942, p. 23.
10. Schroeder Jr., C.F., "Energy T ransfer in Electrostatic Arcs," Proceedings of the Fifth Symposium 011 Electroexplosive Devices , Philadelphia, June 13-14, 1967, The Franklin Institute Research Laboratories, Philadelphia, PA, pp. 2-5.1.
11. Eichel, F. G., "Electrostatics," Chemical Engineering, Vol. 74, No. 6, March 13, 1967, pp. 153-167.
12. Taylor, Boyd C., "Electrostatic~Insensitive Detonator for Precise Synchronization," Proceedings of the Sixth Symposium on Electroexplosive Devices, San Francisco, July 8-10, 1969, T he Franklin Institute Research Laboratories, Philadelphia, PA, pp. 1-10.1.
13. Pitts, L. D. , "Demythologizing Electrostatics," Proceedings of the Sixth Symposium on Electroexplosive Devices, San Francisco, July 8-10, 1969, The Franklin Institute Research Laboratories, Philadelphia, PA, pp. 3-7.1.
14. "Static Electricity," National Fire Codes, National Fire Protection Association, Boston, 1973-74, Vol. 9, No_ 77, p. 144.
15. Tucker, T.J., "Spark Initiation Requirements of a Secondary Explosive," Annals of the New York Academy of Sciences, Vol. 152 Article 1, October 28, 1958, pp. 643653.
16. Hamiter, Jr., L. C., " H ow Reliable are MOS !Cs? As Good as Bipolars, Says NASA," E lectronics , Vol. 42, No. 13, June 23, 1969, pp. 106-110.
17. Smith , W.B., Pontius, D.H., and Budenstein, P.P., "Second Breakdown and Damage in J unction Devices,'' IEEE Transactions on Electron Devices, Vol. ED-20, No. 8, August, 1973, pp. 731-744.
18. Lumley, R.M. and Neiswender, W.J., "Personnel Grounding: A Case History," IEEE Transactions on Industry and General Applications, Vol. IGA-2, No. 5, September/ October, 1966, pp. 417-422.
19. Rose, S .E., "Static E lectricity Can Cause Bipolar IC Failures," E valuation E ngineering, Vol. 10, No. 3, May/ June, 1971, pp. 21-24.
20. Nowac, R.J., "How Not to Get a Charge Out of Static Electricity,'' Machine Design, Vol. 43, No. 21, Sept. 2, 1971, pp. 76-80.
21. " Inhalation Anesthetics," National Fire Codes, National Fire Protection Association, Boston, 1973-74, Vol. 2, No. 56A, p. 5fi.
22. Stroh, D. G. , "Stat.ic Electricity Can Kill Transistors," Electronics, Vol. 35, No. 1, Jan. 12, 1962, p. 90.
23. Hedlund, C.F., "Static and Lightning Protection Grounding." IEEE Conference Record of 1970 Joint Technical Conference on Indus trial and Commercial Pow er Systems and Electric Space Heating and Air Conditioning, Institute of Electrical and Electronics Engineers, Document 70C 8-IGA, New York, 1970.
ELECTRONIC DESIGN 7, March 29, 1976

200

"!:::';

100 80

0> 60

..J
;<::( 40
.zw..
~ 20

a::
0
~ a:: ~
0

"<(
w
Q.

CONDUCTIVE SHOES ON
CONDUCTIVE FLOOR ( 0. 95 M .Cl.)

RELATIVE HUMIDITY : 4 %

10

IOO

WRIST-STRAP RESISTANCE , M.Cl.

1000

6. Operator-to-ground shunt resistance affects the pta~. voltage generated whe n the operator walks . As the resist · ance increa ses , less and less of the voltage can leak off .

.......,._ SOLVENT SYSTEM A (SEE TABLE 4 ) : + V -ll-ll- SOLi/ENT SYSTEM B (SEE TABLE 4) : - II
® SOLi/ENT SYSTEM C (SEETABLE4) : + II

·O)
~-

- - - 0 FlDW
RATE : I. 9ml/ s

50·k0-m UPPER LIMIT FOR STATIC CONTROL

NUMBERS ON CURI/ES RERESENT "lo ETHANOL

10'-~....L."*'".L---'-~~~~~"-~~~~--L~~~~~~

10

15.7 1()2

SOLVENT VOLUME RESISTIVIT Y. k 0. - m

7. Spray cleaning solvents, depe ndi ng upon th eir re ·
sist ivity, can affect stat ic charge generation . Et hanol, with its low ~es i st i v i ty , helps mini mize t he potenti al buil d·
up and th us the st ati c damage.

85

~©W Progra··able Calibrators WDfi[fi] [p@w®o

A precision source for Voltage and Current from one instrument!

_/'

·Output ± 1µ.V to ± 200V and ± 1µ.A to± 200mA.
· Short Circuit Protection on all ranges
· Keyboard Lockout prevents accidental program changes
· Compliance Voltage Limiting for intrinsic safety
· Transient-Free Output, even during start-up and switching.
DigiTec's Precision, Programmable, DC Voltage/Current Calibrators provide the extra power required in today 's automatic systems. Interface is simplified because DigiTec offers a choice of three types of TTL compatible remote programming or a remote keyboard. All these important features and more are furnished as STANDARD on DigiTec Calibrators.

Model 3110, front panel controls for general use.

Compare other leading manufacturers sources with a DigiTec Voltage/Current Calibrator for output and features.

FEATURES

DIGITEC DIGITEC

3210/3220 3110

SD

EDC

Remote Programmable

Yes

No

Yes Yes

Voltage
Mode Max. Current

± 200V 200mA

± 100V ± 100V ± 10V 100mA 50mA 50mA

Current Mode

± 200mA ± 100mA None None

Accuracy

0.01%

0.01%

0.008 %

0.005% < 10V

Display

LED

LED

Nixie Binary

Cost

$1 ,595 $1,095 $2,140 $1 ,925

Call Dick Dale for complete specifications (513) 254-6259

Model 3110 (Front Panel Control)SI095.
flJ95. Model 3210 (Remote Keyboard) ..

·1595. Model 3220

·

(Remote Programmable) .......

Diguec

UNITED SYSTEMS CORPORATION
918 Woodley Road· Dayton , Ohio 45403 ·Ph : (513) 254-625 1 ·TWX : (81 0) 459-1728

These instruments available under GSA contract GS-OO S-27741.

FOR INFORMATION ONLY CIRCLE #281
86

FOR DEMONSTRATION ONLY CIRCLE #282
ELECTRON IC D ESIGN 7. March 29. 1976

SOMETHING NEW for the Efficient World of High Frequency Power Switching!
OK, you Power Schottkys,
the heat's on. .Talk!

1N6098
lJ. =+11s0 c ~
t-+-+-
~ 1101--t--+--+--+---+---+--t--+---+----<
E -1 ~ 8~llf--+-+-+-+--+--~z~-1--1--1
.!!:
_,,,,
0 t:!::~~ti:::::l:::t::±::j 0 o.1 04 0·6
VF-Volts

1N6098

10 0

~

' 0

* <
E

,z00 1/It"'

s

Tj=+J25°C ~

2

'·.al
05
0 S 10 1S :a.o U JD 15 '10iS SD

VR-Votts

These new TRW Power Schottkys have quite a story to tell and it starts with the fact that they're JEDEC registered . Then they'll tell you that they let you maintain 50 Amps-typically 0.55 Volt forward drop at a Tj of 125° C. The highest operating junction temperatures, lowest reverse leakage typically less than 200m A @ 40V, 125° C, and highest voltages on the market today. (Yet, for all that , they're competitively priced.)
Yes, TRW's Schottky Diodes are now1N registered . And they're about to be JAN and JANTX qualified.
Let these new Power Schottkys take your heat, try one in your present circuit or in the circuit you're working on , you'll find out they 're not just talk.

1 N6095

25 AMP

30V

D0-4

1N6096

25 AMP

40V

D0-4

1N6097

50AMP

30V

D0-5

1N6098

50AMP

40V

D0-5

If you'd like to hear more about how TRW's Power Schottkys can help you in the design of lowvoltage, high-current power supplies, call John Power at (213) 679-4561. Or use the coupon (These components are available from stock from our distributors.)
r---------------------, TRW Power Semiconductors An Electronic Components Div1s1on of TRW , Inc., 14520 Av ia tion Boulevard, Lawndale , California 90260 D Please send me data sheets on TRW 's Power Schottky Diodes O Have a salesman get in touch with me
Name
Company Name
Pos1t1 on
Add ress
LC-ity~--------S-tat-e -----Z-ip---~

TRWPOWER SEMICONDUCTORS

ELECTRON IC D ESIGN 7, March 29, 1976

87

TECHNOLOGY

Need an adjustable crystal oscillator?
With properly proportioned circuit capacitances, a crystal
oscillator can be "pulled" over a usefully wide range.

The frequency stability of crystal oscillators is both an advantage and a disadvantage. The advantage is obvious; the disadvantage arises when you wish to deliberately shift the frequency of a crystal oscillator to make small changes in its frequency. These changes are required in circuits such as frequency-modulation systems and phase-locked loops, and where precision timing adjustments must be made, as in watches, digital interval counters and frequency meters.
Various methods of "pulling" the frequency of crystals have been employed. Those using coils or active circuits that emulate coils can be shifted over the largest frequency range, but frequency stability is relatively poor. Inductive pulling elements are unstable, and the crystal operates where the slope of its reactanoe vs frequency is relatively shallow. Variable-capacitance loading of quartz resonators, however, provides superio·r performance.

A crystal has two resonance modes

The equivalent circuit of a capacitance-loaded

lossless quartz crystal i·s shown in Fig. 1. The

crystal's mechanical inertia is represented by L 1

and its mechanical compliance by C1. The elec-

trical capacitance of the crystal and its holder

is represented by C0 and the capacitance of the oscillator's input circuit by C,.

A crystal can resonate in two modes: a series,

and a parallel, or antiresonant, mode. The par-

allel-mode resonance frequency is slightly higher

than the series mode; thus in the parallel mode,

the mechanical element of the crystal behaves

effectively as an inductive reactance that reso-

nates with the capacitive reactance of C0 and Cv in parallel.

The reactance of the mechanical element is

1 X m=wLi - -wc1.

(1)"

Since

(2)

Frank W. Noble, Electronics Engineer, Laboratory of Technical Development, National Heart and Lung lnsti· tute, Dept. of HEW, Bethesda, MD 20014.

88

- - - - r - - - - - ~L~T-;IC-;_

1

I

I

I

Lo

I

I

I

I

I

Cl

I

I

I

I

I

I I

I

L ____ _J L_ - - - - - - - - - - - - ...J

._1---RESONATOR----l

l--osctLLATOR--l

1. A crystal-resonator's mechanical parameters are
loaded by the inherent electrical capacitance of C -the 0
crystal and its holder-and the oscillator's input vari·
able capacitor, Cv.

where wo is the series-resonance frequency of the crystal, substituting Eq. 2 into Eq. 1 yields

(3)

= If we let w = w0 + Aw,
so that ·W 2 (J)"lo + 2w0 (Aw),

(4) (5)

and substitute Eq. 5 into Eq. 3, then

= X m 2 L , (t.w),
= because w w0 ·

(6)

At parallel resonance, the reactance of the

mechanical branch, X m, equals the reactance of

C0 and Cv in parallel. Thus from Eq. 6,

(Aw) =

l

2woL 1 (Co + Cv)

(7)

Substitute Eq. 2 into Eq. 7 and rearrange to get

C1

r l (Aw) (A f)

Co

~-~- 2 1 + ~:

(8)

An electromechanical coupling factor, r 0 , determined by the crystal cut and method of mounting can be defined as

r o:= cC,o·

(9)

ELECTRONIC DESIGN 7, March 29, 1976

0 .6 0 .5 0.4 ~ >0 .3
0 .2 0.1

0

2 4 6

8 10 12 14 16 18 20

Cma11. Cmin

2. The maximum possible value of the frequency devia-
tion factor, y, is a function o-f the ratio Cmaxf Cm iJl of
capacitor C,. and is obtained when C0 = \/ C:iax cm ;-;;:

8.>..

J: 0 .8

u

4
a

-i

o.6

>-E >-

~ ~ 0 .4

OllL--'-~'---'-~'---'-~,___.._~,____..___,
0 ru ~ m M M ~ w M M
FRACTION OF OPTIMUM C0 (l)
3 . The fraction of y,,,.. , that is attainable when the crystal capacitance, C0 , is not the optimum value is not strongly
affected by the Cmax f Cmi 11 ratio, as shown by varying the
ratio over a range of 3:1.

Eq. 8, expressed in kHz/ MHz for convenience,

can now be written as

(b. f) -

5oo kH / MH (10)

fo - [

Cv] Z

z,

r.0 l+Co

or

(.b. f) max

(11)

and

(b.f) mi11 =

500 f 0 [ C ]"

(12)

r o 1 + ~i:x

Let's define the pulling range, B, as

B = (b.f) max - (b.f) mi1u

(13)

then

(14)

Maximizing the pulling range To maximize the pulling range, we let the func-
tion within the brackets of Eq. 14 equal y and
ELECTRONIC D ESIGN 7. Ma rch 29, 1976

then differentiate to get

a y

Cmi11

aCo - [Co + Cmi11 ] 2

C max [Co + Cmax ] 2 ·

(l5)

Setting Eq. 15 to zero and solving, yields the con-

ditions for the maximum pulling range,

(16)

when C0 is the geometric mean of the Cv extremes. Then

=I j~ j~J. Ym·· 1 +

l +

(17)

l C11iax

Cm,11

A plot of Eq. 17 is shown in Fig. 2. However,

practical circuits generally yield a smaller pull-

ing range than allowed by Eq. 17, because the C0 for standard crystals is usually too small to satis-

fy Eq. 16, even when care is taken in the oscilla-

tor design.

Calculations show that the value of Cmaxl C111i1.

does not strongly affect the percentage of Ymax

that is achievable as C0 is varied below its optimum value as given by Eq. 16.

A practical example

To gain a quantitative "feel" of magnitudes we

are dealing with, let

= Crnax Z Cmi11 ;

(18)

thus the optimum value of C0 from Eq. 16

becomes

Co = Cmi11 Vz

(19)

and Co = Cmax/ Yz

(20)

Fig. 4 contains a replot oif Fig. 2 along with

Cmi11 / Co and Cmax/ Co. Now we can solve a practical problem: How

to achieve 5-kHz deviation from an AT-cut 7-

= MHz crystal that has r 0 250, C0 = 5 pF and

Cmi11 = 7 pF.

= First assume that C0

V Cmax Cmi11 can be

achi-eved. Then from Eqs. 14 and 17,

£B:"" = 2Ymax = 75

(21)

and
Ymnx = 0.357
From Fig. 4, scale C we get,

Cmax = 4.45;

from scale A,

C min

c:-- - . Cmi11 - 0 475'or Cmin -- 2·37 pF ·'

and from scale B,

= Cc:x 2.12, or Cmax = 10.6 pF.

An oscillator with a Cmin as small as 2.37 pF is difficult to achieve; practically, C"' i11 tends to be about 7 pF, even with very careful design.
Of course, the optimum condition, Co= V Cnrnx Cmin,
is therefore not achieved. Nevertheless, with a CmaxlCrnin larger than the

89

Now you can ''see" inside your 8080 with
the Ramtek MM80

A A ..&. . - - - - - - - - - - - - - - - - - - - ,
0 .6
5 05
0.8 4 0.4
Q.6 3 0.3
0.4 2 0 .2
OZ I 0 .1
I 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Cmo1 Cmin
4 . Design curves for the optimum case, where C = 0
v'C1111" C11, ; 11 , can be used to solve practical problems .

Develop and debug 8080/8080A hardware and software-
using the real engineering prototype.

Fast and convenient softwarewith ROM resident assembler and editor.

Service and debug 8080 systems in the field with a sixteen pound package.

Easy program modification during development -
with the PROM programmer.

Get "inside" your 8080 breadboards and know where you are every step of the way-
without building special front panels.

RAMTEK's new MM80 in circuit Emulator plugs directly into a 8080 microprocessor socket with its own 8080, giving you complete system access through a full complement of console commands, front panel controls, displays and probe points . With the MM80, you actually "see" what's going on inside the system.
The programmer can step, trace and breakpoint the software in the real system, and display and alter the 8080 registers , memory and I/O ports even if the user programs are all in ROM.
The MM80 provides a complete control and test center for any system under test. Five scope probe points let you trigger on MI, sync, ¢1 , ¢2 signals and specific address references. RAM diagnostic programs are provided . The LED display provides complete processor status information.
For the complete inside story on Ramtek's new MM80, call or write

RAMTEK CORPORATD'J
THE GRAPHIC DISPLAY COMPANY

RAMTEK MICRO MACHINES 292 Commercial Street
Sunnyval e, CA 94086
Tel (408) 735-8400

The Ramtek MM80 is available

TWX 910-3 39-9379

now from Texas Instruments Supply.

CIRCLE NUMBER 41
90

2 .5 mH

.-----~-~---,tF--.,_.--..--.._-......-t~T

c:::J 6 MC
HC-6

470k

50pf
.__--4,___, 0.005J.LF

5. A practical oscillator circuit that can achieve 5-kHz deviation from a standard 6-MHz, AT-cut, HC-6 crystal resonator uses a dual-air-variable capacitor.
theoretical value 4.45, the deviation range can still be achieved.
Assume that a CmaxlCmin of 10 can be obtained
= readily; thus Cmax 70 pF. Then the correspond-
ing Ym.ax from Fig. 2 is 0.520 and B/ f 0 = 1.04, from which the deviation for the 7-MHz crystal results in 7.28 kHz.
= Since we need y 0.357, the value of y / y "'"'
is 0.686-considerably removed from the opti-
= mum condition. With Cm.ax 70 pF, the optimum
value of C0 for tMs oscillator becomes 22.1 pF. Generally, to achieve optimum conditions for
pulling, you should use special crystals that have plated areas larger than twice the diameter for standard crystals.
A practical oscillator circuit is shown in Fig. 5. In the interests of achieving a small minimum value for C,., the circuit uses a dual-air-variable capacitor with its sections in series.
This configuration reduces the minimum value of C,. by more than half that of a singlecapacitor arrangement. Maximum capacitance is also less than half the maximum capacitance of a single capacitor, but this is not important because an adequate C,nax/C111 ; 0 ratio can readily be achieved with standard components. ··
ELECTRONIC D ESIGN 7. M arch 29. 1976

Perfom1ance and Value through advanced engineering

Model 134
3¥2 Digit DMM $189.00
Competitively priced with the best analog meters, the Model 134 provides digital accuracy and an easy-to-read 1/2 inch digital display. The Model 134 is an ideal, low cost lab or production test instrument .
The Model 134 measures DC volts, AC volts, DC current, AC current and resistance with a basic accuracy of ±.2% through a total of 22 range scales.
It features auto-decimal positioning, auto-polarity, 100% overranging, high voltage protection circuit, probes and a one year warranty.
The Model 134 is the logical alternative to analog instrumentation at a competitive price.

Model245
Portable, 4V2 Digit DMM $295.00
Ideal for field use, the Model 245 is a rugged, truly miniature, lab-quality, 5-function instrument featuring a basic DC accuracy of ±0.05%, .005% resolution, 100% overranging, equipped with both rechargeable battery pack and battery recharger/line adapter.
Model 245 measures ACV (lOOµV to 500V RMS), DCV (lOOµV to lOOOV), Resistance (100 milliohms to 20 Megohms), AC and DC current (1 microamp to 2 Amps) . AC voltage/current response, 30 Hz to 50 kHz.
With over 25,000 in the field the Model 245 is still the only pocket-size portable 41/ 2digit DMM available.

Model 1455
Bench/Portable 41/2 DMM $.355.00
Model 1455 - all the virtues of a laboratory bench instrument with the added benefits of complete portability.
A five function multimeter featuring 1/ 2" high display, 100% overranging, measures 100 µV to 1000 VDC, 100 µV to 500 VAC; resistance 100 milliohms to 20 Megohms ; AC and DC current 1 microamp to 2 amps. AC response, 30 Hzto50kHz.
Basic accuracy on DCV is ±0.02% reading ±0.01 % f.s., ±1 digit for 6 months. Internal NiCd battery module and recharger. Model 1450 4¥2 Digit DMM $.325.00
The same specifications and features as the Model 1455, line operation only.

MOOll '\)<I O I0 1T· l M U lflMITI~

~ 7 75

o:~·a·-····· -:"·o··'"·:":n --

... . -."'

"'"

Model3400
System/Lab 4¥2 Digit DMM $795.00
Model 3400 is the world's most accurate systems/lab 4 V2-digit multimeter. It is a fully programmable system multimeter and a highly versatile stand-alone, autor.anging laboratory multimeter. Remote triggering will allow 12 conversions per second.
Full 100% overranging (20,000 counts), basic DCV accuracy of ±0.007% of reading ±1 L.S.D. for six months, measures from 10 microvolts to 1,000 VDC (ACV from 10 microvolts to 750V RMS), resistance from 10 milliohms to 20 Megohms; AC/DC and DC/DC voltage ratio.

Model3500 Model5740

511z Digit DMM $995.00

Multifunction Counter $295.00

The Model 3500 delivers more features for less money than any other 51/2 digit DMM available . It is a full function, autoranging DMM with 6 months basic accuracyof±0.007% ofrdg. ±0.001% f.s. ±1 L.S.D. Remote ranging and trigger, 20% overrange and 1/ 2 inch planar displays.
· DCV lµV to 1000 volts · ACV lµV to 700 volts RMS . 30 Hz to 100 kHz · Resistance 1 milliohm to 12 Megohms · 1000 MQ Input Impedance through 10 VDC · RatiohmicT.M. Resistance
Method 2 and 4 wire. BCD output and voltage ratio are included at no extra cost.

Model 5740 measures Frequency, Period, Period Average, Total Events and Elapsed Time.
SPECIFICATIONS: Sinewaves, Square Waves, Pulses, Pulse Pairs, Complex Waves· Frequency: 5 Hz to 100 MHz; 10 ms/100 ms/1 sec./10 sec. gate times, resolution to 0.1 Hz· Period : 1/ 2 microsecond to 0.2 sec.· Period Average: .10, 100 and 1000 periods · Total Events: 0 to 9,999,999 (unlimited with "overflow" indicator) · Elapsed Time : 0 to 99,999.99 sec. (27.8 hrs) · Sensitivity to lOmV

. 00
- I 0 2 5 78 . · : i:

for complete information on these and other Data Precision instruments or a demonstration, contact your local Data Precision representative or Data Precision Corporation, Audubon Road, Wakefield, MA. 01880
(617) 246-1600. TELEX (0650) 949341.
~-1:,ATA PRECISION
...years ahead

CIRCLE NUMBER 42

EL EC TRON IC D ESIGN 7. Marc h 29 , 1976

91

Ideas ior Design

A versatile CMOS circuit changes mode when bias and load are changed

The CMOS circuit of Fig. 1 can perform many electronic functions, depending only on the circuit's applied bias and load. The circuit can be used as an amplifier inverter, amplifier follower, frequency doubler, oscillator, or a multivibrator. Though over 20 such versatile circuits have been developed,' the circuit in Fig. 1 is particularly practical, simple and easy to apply. The circuit can also be designed in IC form.
The circuit's functional versatility is made possible by its special I-V characteristics, with analytic properties .that satisfy conditions for several electronic functions on the same portion of the I-V plane.
For example, in the I-V plot of Fig. 2, the point I = 3 mA, V = 11.2 V can be obtained when the bias, e, is either 3 or 1 V. At this point, the transconductance, aI/ ae, is positive or negative, depending on whether e is 3 or 1 V, respec-
tively. For al/ ae > 0, the circuit can work as an amplifier follower, and for allae < 0, as an in..
verter. The circuit is a three-terminal combination of
two n-channel and two p-channel MOSTs. The particular choices of depletion-type n-channel

devices, FT 57 and 2N3796, and the 9-V threshold battery for the .p-channel FT702 unit determine the curvature of the characteristic curves and the location of the zero-bias curve on the I-V plane (Fig. 2). Further modification of th~ curves can be obtained by the insertion of another battery in series with the gate of the other FT702.
The circuit operates as a follower amplifier when it is biased ate= 3 V, E R= 15 V and load
resistor, RL, equals 1.2 kn. With the same RL and
Ell, but w.ith e = 1 V, the circuit operates as an amplifier inverter. With the load line, where
R,, = 76.2 n, ER = 10.4 V and e = 2 V, the cir-
cuit is a frequency doubler. But with the same load line and e = 1 \V, the circuit is again an inverter, and with e = 3 V, a follower.
With load line C, RL = 567 n, Ert = 5.5 V, and
with an appropriate .inductor in series with R L, the circuit behaves as an a.stable multivibrator when e = 0. With an LC circuit connected, the circuit works as a quasi sine-wave oscillator. And when e = 2, 3 or - 4 V, the circuit works as a monostable multivibrator. The circuit's signal input terminals can be used for trigger pulses.

+V 3V

FT57

FT70Z

+
SIGNAL OR
TRIGGER INPUT
I
e-81AS VOLTAGE

1-mA

BASIC VERSATILITY
I. AMPL. INVERTER Z. AMPL. FOLLOWER

3. FREQ. DOUBLER 4 . MULTMBRATORS
(AU. THREE MODES)

1. A circuit made with four CMOS devices becomes a versatile circuit whose properties depend only on the load and bias values.

92

20 V-VOLTS
2. The characteristic curves of the CMOS circuit provide properties for amplification, inversion and multivibrator operation, all on a single .l·V plane.
ELECTRONIC DESIGN 7, March 29. 1976

Triplett 310 mini·VOM's
fit your hand and your
wallet ...
onlyS
The high quality Triplett 310 is a little all-in-one VOM. This made in the U.S.A. VOM gets around a lot for half fare. It packs most of the features you'd expect to find only on a meter twice the size and price. It fits in your shirtpocket easily. The small size and Its versatility is a boon to field servicemen as well as circuit designers, technicians, electrical maintenance engineers, and the price is right for vocational and hobbyist use. A newly designed high impact, drop resistant case makes it practically indestructible ... 20K ohms/volt DC and SK ohms/volt AC ranges provide plenty of sensitivity for most applications ... and, there's diode overload protection with a fused R X 1 ohm range. The single range selector switch is a real time saver for reading 0 - 1200 DC or AC volts, 0 - 20 megohms, and 0 - 600 micro-amps or 0 - 600 mllliamps at 250 millivolts. Comes complete with 42" leads, alligator clips, batteries and instruction manual. Accessories triple the versatility of a 310. Adding the Model 10 clamp-on ammeter allows you to measure AC currents easily with one hand. Visit your local distributor or Mod Center and shake hands with a real bargain.
THE MARK OF
- TRIPLETT
QUALITY BLUFFTON, OHIO 45817
Triplett. The easy readers
CIRCLE NUMBER 43

IDEAS FOR DESIGN

It is perhaps easier to follow the circuit's vari-
ous functions with Fig. 3. This transfer characteristic curve shows the circuit's versatility comprehensively. With R 1, = 5 kn, biasing in the AB region makes the circuit an amplifier inverter, and biasing in the BC region makes it a follower. Note that as a follower, the circuit has gain,
aV/ ae > 2.
The complete loop, ABCDE, traces the circuit's behavior in oscillator and multiv.ibrator applications. Biasing at point B gives frequency doubling, but with RL = 5 kn, the ABC part of the curve is not symmetrical and would provide a distorted output. To optimize frequency-doubling action, the curve can be made more symmetrical by changes in R L and the threshold voltage.

Reference

1. Lubelfeld, J., "Versatile CMOS Circuits," Air Force Institute of Technology, WPF AB, OH 45433, internal report.

J. Lubelfeld, Dept. of Electrical Engineering,

Air Force Institute of Technology, Wright-Pat-

terson AF Base, OH 45433.

CIRCLE No. 311

15

RL · 5k 10 V- VOLTS
B 5

E

0

- 10

-5

0

D

5

10

e-VOLTS

3 . A transfer characteristics curve for RL = 5 kn clearly shows how the different bias voltages, e, provide the different functions and modes.

Digital frequency doubler works to 100 kHz

A digital frequency doubler that works from

1 Hz to 100 kHz can be built with only one hex-

inverter chip, two diodes and a capacitor (Fig. 1) .

The circuit requires a square-wave input. To

produce an approximately symmetrical output,

the capacitor, C, should have a reactance of 1000
n at the input frequency. If symmetry is im-

portant, the capacitor may be padded with a ser-

ies or parallel resistor to provide almost perfect

symmetry at the frequency used.

The output circuit includes inverters G3, G., G,, and GHthat are cross-coupled by diodes D1 and

Dt. The input signal is split into two components

that are phase-shifted 90-degrees from each other

with the help of inverters G1 and Gt. and capaci-

tor C. The two shifted signals are combined to

provide a doubled-frequency output.

The circuit is very stable and several stages

can be cascaded to a frequency limit of about

100 kHz.

Gerald L. Vano, Systems Engineer, Alden R e-

search Fo undation, 117 N. Main St., Brockton,

MA 02403.

CIRCLE No. 312

94

c
DI 02

OUTPUT 21 ;

GI TO G6 - 1/6 MC 940 P DI. D2 - IN914 Xe OF c · 1ooon
1. A simple digital frequency doubler built with a hex·inverter can operate from 1 Hz to 100 kHz .
ELECTRONIC D ES IGN 7, March 29, 1976

THE HIGH VOLTAGE SUPER GROUP.

Type
Slim-Mox
ri
Mini-Mox

Resistance Power Rating

Range

At70C

1 MO to SOOO MO

SW

18,000 v ±2SO ppm

lOOko

.2SW

to 10,000 Mo to 1.4 W

1000 v
to SOOO V

±lQQ ppm to ±1000 ppm

Length 2.08
Height .84
Thickness .860
Length .470 to 1.310
Dia . .140 or .16S

Divider-Mox

4.SMO

l.S w

to 2000 MO to 6.0 W

7.S kV to 30kV

±lQQ ppm to

Length

± 1000 ppm overall 2.2 to S.2

TCR Tracking

Dia .

±2S ppm

.34S

Maxi-Mox Power-Mox

10 kO

LS w

to sooo Mn to 12.S W

7.S kV

±lQQ ppm to

to 37.SkV ±SQQ ppm

20 kn

22 .S w

to 1000 Mn to 4S W

20 kV to 4S kV

±lQQ ppm to ±JOO ppm

Length 1.122 to S.2
Dia. .310 or .34S
Length 3.96 to 6.96
Dia. .89

ELECTRONIC D ESIGN 7. March 29. 1976

CIRCLE NUMBER 44

What's Economy? bility? Better talerance? Here's o e solution to all of the above. The Victoreen MOX high voltage resistor line. From Mini-MOX to Power-MOX, you'll find that the people at Victoreen know how to make you happy. We know how to give you resistor performance that allows more design flexibility. And product reliability. MOX resistors are the high voltage designer's solution to problems caused by other resistors. The tougher your high voltage resistor requirements, the more you need our advanced, reliable MOX magic.
Send for complete technical data. Write: Victoreen Instrument Division
10101 Woodland Avenue, Cleveland, Ohio 44104
IUUISHELLER-GLOBE CORPORATION
95

High-frequency zero-crossing detector operates beyond 50 MHz

The three sections of an MC10116 ECL. receiver when connected in tandem make a sensitive zero-crossing voltage detector that is capable of operation beyond 50 MHz (Fig. 1). Input voltages of this detector may range from 30 mV to 5 V, peak to peak. The zero-cross point does not change by more than 2 ns over this large input range.
The MC10116 chip contains three differential amplifiers, each with a gain of approximately eight; thus the over-all gain of all three stages in tandem is 512. Input biasing is derived from the negative 1.3-V reference-voltage delivered at pin 11 of the chip. This voltage centers the de of the input amplifier for class-A amplification and maximizes its common-mode-rejection capability.
For input signals less than 100 mV the first

amplifier stage operates in a class-A mode.

Larger signals force all stages into a fully

switched mode. Propagation time through one

stage is about 2 ns in the switched mode, and less

in class A. Since only the first stage ever operates

in class A, the propagation time difference be-

tween the smallest signal, 30 mV, and the largest

signal, 5 V, will vary only by the difference be-

tween the class-A and switched-mode delays-

much less than 2 ns.

The value of input resistors R1 and R2 can be

chosen to match the line impedance. And the val-

ues of the coupling capacitors, C, should be se-

lected in conjunction with R1 and R2 to provide the required low-frequency response.

William A. Palm, Principal E ngineer, Magnetic

P eripherals Inc. , 7801 Computer A ve., Minne-

apolis, MN 55435.

CIRCLE No. 313

270

270

270

c

I

9_ _ _ _ _ _ _ _ ~

'~------- ~

9--- 3--- iO-------- 7

270

270

13__ _ _ _ _ _ _ _ 15 270

A high-frequency zero-crossing detector operates over a wide range of inputs-from 30 mV to 5 V,

peak to peak. The circuit triggers at the crossing point within 2 ns over the total input range.

IFD Winner of November 22, 1975
Douglas Thom, Development Engineer, Novu s Div., Nati onal Semiconduct0>r Corp., 1177 Kern Ave., Sunn yvale, CA 94086. Hi s idea, "Capa cit or Drops Voltage with Little Heat for LowCost, Low-Voltage Power Supply" has been voted the Most Valuable of Issue Award.
Vote for the Best idea in this issue by circling the number of yo.ur selection on the Information Retrieval Card at the back of this issue.

SEND US YOUR IDEAS FOR DESIGN. You may win a grand total of $1050 (cash)! Here's how. Submit your IFD describing a new or important circuit or design technique, the clever use of a new component or test equipment, packaging t ips , cost-saving ideas to our Ideas for Design editor. Ideas can only be cons idered for publication if they are submitted exclusively to ELECTRONIC DESIGN. You will rece ive $20 for each published idea, $30 more if it is voted best of issue by our readers . The best-of -issue winners become eligible for the Idea of the Year award of $1000.

ELECTRONIC DESIGN cannot assume responsibility for circuits shown nor represent freedom from patent infringement.

96

ELECT RONIC D ESIGN 7, Ma rch 29 . 197 6

®~

l'I, L01ffJRS l'OIJR TOTAL ll\1S'r1'LLED COST.
What are you looking for today in circular connectors?
Fast delivery, for one thing , so you don't have to carry a lot of inventory High quality, for another, so you can cut down on rejects and returns. And the exact right connector, too, so you can design more efficiently.
Delivery, quality, selection ... they're all part of your total installed costyour real cost. Cannon can lower it.
Why? Because we offer you the largest network of stocking/assembling distributors. The broadest line anywhere. The product with the best reputation for quality in the industry.
E u C' TRO NI C' D1 s 1GN 7. March 29. 1976

After almost sixty years of experience we can proudly say, few products are made as well as Cannon makes circular connectors.
K Series Quick Connect/Disconnect Connector Ac me th read · 1-75 contacts· 0-20 wire sizes· Coaxial contacts available.
KO Series Miniature Version of K Series Meets environmental requirements of MIL-C-25955 ·Solder contacts· Diecast aluminum shells.
KPT/KPSE (EnvironmentResistant) Qualified to MIL-C-26482 ·Solder contacts (KPT), crimp contacts (KPSE) · Bayonet coupling .
MC Series Environmental Subminiature Connectors Solder contacts· Diecast aluminum shells·
CIRCLE NUMBER 45

Polychloroprene insulators. MS Series Connectors to MIL-C-
5015 1-100 contacts · Solder termination· Threaded coupling
Applications: Rapid transit · Traffic control · Machine tools · Medical electronics· Recreational vehicles · Business aircraft· Mining machinery and instrumentation.
Today, send for "Cannon Cost Cutters" brochure. Contact ITT Cannon Electric, 666 East Dyer Rd ., Santa Ana, California 92702. (714) 557-4700.
Ut~l\101\1
El\1G11'1EERl1\1G L01t'ERS l'OIJR COSTS.
CANNON ITT
97

International Technology

Nonvolatile MNOS memory has longer operating life

A nonvolatile semiconductor memory that overcomes the short life of the conventional MNOS (metal-nitride-oxide semiconductor) transistor has been revealed by the Tokyo Shibaura Electric Co. in Japan. Because the characteristics of the MNOS transistor deteriorate after ea.ch write operation, the lifetime is usually well below 106 cycles.
Standard MOS memory cells are combined in the Toshiba memory with MNOS transistors, and in normal operation the MNOS transistors are not used. Data are written into the MNOS transistors only when nonvolatility is essential, such as to protect against data loss in the event of a power failure. Because the MNOS transistors

undergo a minimum number of write cycles their lifetime is increased.
The major drawbacks at present are that ten transistors are required for each memory bit and costs are likely to be higher than if a CMOS RAM with back-up power supply were used. Current work is aimed at improving yield and increasing the level of integration.
A 64 x 4-bit array is feasible now but Toshiba hopes to achieve a 1 k-capacity in the next year. The 64 x 4 RAM can retain data without power for at least one year, has a read access time of less than 500 ns,. a write-cycle time of less than 1 µs and a power consumption of 600 mW.

Green LED process boosts light output

A new process for producing green light-emitting diodes with luminous intensities of 30 millicandelas at an operating current of 10 mA has been developed by Siemens AG, Erlangen, West Germany. The diodes can operate with up to 60 mA, and at the higher currents the light output is sufficient to illuminate the surroundings.

The first stage in the production of the devices is the direct synthesis of polycrystalline gallium phosphide from pure gallium and phosphorous. This is then converted to monocrystalline GaP on which an n-type GaP layer is grown, at 900 to 1100 C, by means of fusion epitaxy. Further doping with zinc produces the pn junction, which is required for light emission.

640 characters displayed on 40 x 50-cm LCD
A large-area liquid-crystal dis- Tokyo and Asahi Glass. The panel,
play panel has been jointly de-- . which measures 40 x 50 cm, can
veloped by Hitachi, Dai. Nippon display 640 characters (Roman

letters, numerals and Japanese kana characters) and can also be used in a computer-graphics mode. The panel, still in an experimental stage, makes use of matrix addressing.
The individual characters are generated from a 9 x 7 dot matrix. The space between vertical lines is 9 mm, and the space between horizontal lines is 3 mm. Between characters, the space is 18 mm
(vertical) x 100 mm (horizontal).
The liquid-crystal material developed for the panel contains four ionic additives and has an operating temperature range of -10 C to 74 C, a threshold voltage of 6.9 V rms and a cut-off frequency of 3.4 kHz. Contrast ratios up to 25 :1 have been obtained for the complete panel operating with a maximum rise time of 1.5 s and fall time of 0.8 s.
Helicopter rotor blade used as radar antenna
A unique radar that uses a helicopter rotor blade as the antenna has been developed by the Electronic Systems Dept. of Ferranti in Edinburgh, Scotland. The antenna is built into one blade of the rotor assembly and wholly contained within the aerofoil section.
Because of the large span of the rotor blade a very narrow beam in azimuth-about 1/2 degree-is produced. This sharp beam, together with a 50-ns transmitted pulse .and an antenna-rotation speed of 240 rpm, results in a 360-degree planview radar picture of high resolution.
The rotor-blade radar, called Rodar, is expected to extend the operational capabilities of helicopters. For example, the high definition of the radar will enable small objeds, such as survivors at sea, to be rapidly detected in search and rescue operations.

98

ELECTRONIC DESIGN 7, March 29, 1976

All the advantages of optical coupling, plus supersensitivity with high gain, and stability.

Coupled with a light source, Crystalonics' FOTOFETs provide:

Electrically isolated input and output circuitry, with isolation resistances as high as 1015; Capacitances between input and output of less than 0.01 pf; Signals transferred unilaterally, with no reflection of output signals.

As a replacement for phototransistors, photomultipliers and photodiodes, our FOTOFET is ideal for coupling applications that demand high sensitivity and stability.

The FOTOFET is many times more sensitive than conventional bipolar optical devices. with sensitivity adjustable over ranges up to 106 to 1. It produces gallM>andwldlhs 4 times higher and has a realizable power gain in a solid state cfevice.

The FOTOFET remains stable over the operating temperature range and exhibits a stable gain that will not vary with the level of the light source.

Thus, FOTOFET gives you three marked advantages: isolation,

supersensitivity arld stability.

·

And there's a marked advantage in doing business with Crystalonics. For over a decade, we've been helping designers solve their problems. We're known for efficient communications between the designer and our~
engineers. We produce top quality, innovative devices, with you in

Send for our new catalog of FOTOFETs, then, order samptes.
Or for immediate design assistance, give us a call. Ask for Richard Antalik,
our man on FOTOFETs.

We're at your elbow to ease yourdaslgn.

_.,~TELEDYNE

147Sh~~.9o

Tel: (617) 491-1670 ·TWX: 710-320-1196

CIRCLE NU

46

Save Space. Save Weight. Increase Reliability.

Paralleling transistors doesn't pay -not when an inherently rugged single device can do the job far
more reliably, using much less space, weight, and at lower total system cost. That's why PowerTech's unique single-chip NPN silicon high-power transistor is
the one way to go.
Used alone, our space-saving
single-chip device eliminates multiple failure sources while reducing the environmental testing costs inherent in parallel arrays. Because of their simplicity they're available off-the-shelf-pre-rated, pre-tested and inventoried to meet virtually any hi-rel JAN and JAN-TX hi-current requirements without custom prices and long

custom waits. For information, application assistance, and free design guide call Sales Engineering, PowerTech, Inc., 9 Baker Court, Clifton, N.J . 07011; (201) 478-6205.

Type #

(pk .) le Vcoo

JAN-TX 2N5926

90A 120V

PT-7511

90A 200V

JAN-TX 2N5927

120A 120V

PT-6502 200A sov

PT-9502 * SODA sov

350 Watt Power Rating * 625 Watt Powe r Rating Guaranteed SOAR

(hf· = 10)
Vce (sat) @ !£
0.6V @ SOA 0.6V @ SOA
0.6V @ 70A o.7v ® rnoA O.SV @ 300A

SiIicon transistors to 500 amos with lowest VcE [sat J/fr
A(

PowerTech, Inc. 11BIG IDEAS IN BIG POWER"
100

CIRCLE NUMBER 47

ELECTRON IC D ESIGN 7, Maroh 29, 1976

16-k bit RAM has the· same spee·d and lower dissipation/bit than 4-k versions

WE ------r

STROBE

DATA

IN

---+--=::;:_--------! L ATCH

COLUMN LATCH
AO

Al

A2

A3

ADDRESS BUS

A4

A5

AS

ENABLE DISABLE ENABLE
COLUMN DECODER

SENSE AMPS I /0 GATING

OUTPUT LATCH AND
BUFFER

ROW LATCH

ROW DECODER

16384 BIT
STORAGE ARRAY

-----Vea ----Voo ----Vee
----GND

ENABLE

!RAS)

CLOCK GENERATOR NO. I

I ntel, 3065 B owers Ave., Santa Clara, CA 95051. (408) 246-7501. P&A: See t ext .
With the introduction of Intel's 16-k bi1t NMOS random-access memory-the hi ghest density RAM to date--designers can achieve a 4: 1 increase in memory-board density without sacrificing speed and with savings in power.
T he new 2116 offers p.Jug compatibility with 4-k dynamic RAMs like the company's 2104. Both units come in 16-pin packages and employ multipl·exed addressing. And both specify best access and cycle ti mes of 250 and 375 ns, respectively.
Further, the new semiconductor memory dissipates less than 700 mW in active operation and only 12 mW on standby. Compared with Intel's 4-k RAM, the 2116's power

2116 FUNCTIONAL LAYOUT

I

a R/ W 1/0 CIRCUITS

32 · 128 CELL ARRAY

128 SENSE AMPLIFIERS

ROW DECODER
a
DRI VER
CKTS.

32 · 128 CELL ARRAY COLUMN DECODER 6 110 CKTS .
32 · 128 CELL ARRAY 128 SENSE AMPLIFIERS

32x128 CELL ARRAY

ADDRESS BUFFERS 6 TIMING CIRCUITS

specs represent a reduction in dissipa.tion / bi·t by a factor of almost four.
Other features shared by both the 16,384-bit and 4096-bit RAMs include operation from power supplies of 5, - 5 and 12 V, similar supply-current requirements, and TTL inputs and outputs. Also, they

can both be refreshed in 64 address cycles, and have the same refresh interval requirement of 2 ms.
The pinouts of t he two 16-pin RAMs are identical, with one exception: The A6 address input of the 16-k RAM replaces the chipselect (CS ) input of the 4-k RAM . The 2116 has seven address inputs, and the 2104 has six. Other pins are the same: co lumn-address strobe ( CAS.) , row-address strobe (RAS), write enable (WE ), threestate data output, data input and supplies.
Intel has also developed the Model 3242 address multiplexer and refresh counter for use with the 16-k RAM. It converts a 14-bitwide address into the 7-wide multiplexed column and row addresses, and controls either 64-cycle or 128cycle refresh. (The latter is also possible with the 2116 ) . The 3242 comes in a 28-pin DIP.
The 16-k bit memory employs a single-transistor storage cell and uses the company's n-channel silicon-gate MOS technology. The cell design differs from the 2104 in two major iiespects: two layers of polysilicon are used for interconnections instead of one, and bit-cell lines are diffused, not deposited metal.
The chip-design changes halve cell area to 13 x 35 µm and reduce cell capacitance to 0.03 pF.
The resulting chip measures 145 x
235 mils, or about 34,000 square mils-only about twice that of some 4-k RAM chips.
Power dissipation has been kept low by several techniques. For example, half the memory is inactive during operation. Also, sense-amplifier load devices are shut off as soon as the write or restore operation is completed.
Though operating as a 16,384 X 1-bit RAM , the 2116 is divided into
( continued on pag e 102 )

ELECTRONIC DESIGN 7, March 29, 1976

IOI

INTEGRATED CIRCUITS
1 continued from pag e 101 )
two 8-k RAMs that share a column decoder (see functional layout) . Each 8-k RAM has two 32 x 128 cell arrays, which in turn share 128 sense amplifiers.
In normal operation, A6 selects one of the two 8-k RAMs, and the other 8-k RAM is kept inactive to conserve power. Address lines A0 to A,, and the strobe inputs select the bit in the active half. The strobe inputs drive internal TTLto-MOS level converters and clock generators, which time internal operations. For increased operating voltage margins, address and data inputs as well as the CAS and RAS inputs, have been augmented with on-chip latches.
A special refresh mode was developed to achieve 64-cycle refresh -the usual amount for a 4-k RAM because of its 64 x 64-cell array. The 2116 is typically a 128 x 128 array, but to require 128 refresh cycles for the 16-k RAM would reduce the availability of memory to the system.
The refresh signal is multiplexed onto the CAS input at the RAS transition. The output then goes to the high-impedance state. A6 is ignored, and all cells on the selected word line are refreshed in both 8-k RAMs. Thus, 128 x 2, or 256 bits, are refreshed simultaneously and only 64 cycles are required. For 128-cycle refreshing, read cycles· can be used, or alternatively, the RAS input can be used to control row-by-row refresh.
Intel plans to produce a family of 16-k RAMs based on the 2116 design. Three versions have been specified to date: The standard 2116 has maximum access time of 350 ns and a maximum read or write cycle time of 500 ns. A dash-2 version provides the top access and cycle times ( 250 and 375-ns maximum). Finally, a dash-4 version offers maximum times of 300 and 425 ns. All of these times are identical to those of similarly labelled Intel 4-k RAMs.
Production quantities of the 16-k RAM are expected by the middle of the year. Initial prices are $50 for quantities of 50 to 100. Intel says production volumes will reduce 16-k memory costs to 0.1 ¢/bit by the middle of 1977.
CI RCLE NO. 30 5
102

4-k RAMs have 200-ns access
Advanc ed Micro D ev ic es, 901 Thompson Pl., Sunnyval e, CA 94086. ( 408 ) 732-2400. $15.30 to $21.60 ( 100) ; stock.
A pair of 4096-bit dynamic RAMs features access times to 200 ns and maximum power dissipation of 750 mW (at 0 C) . The RAMs are available in a 22-pin package with separate data input/ output circuitry-the Am 9060-or in an 18pin version with common data input/ output circuitry-the Am 9050. Both devices require only a single clock, and all inputs and outputs except clock are TTL compatible. The RAMs' input circuitry provides a purely capacitive load, so that during chip-enable transitions, memories don't experience extraneous current surges. Also, both units guarantee zero-data and read-hold times with respect to the chip-enable pulse. Thus data can be changed at same time chip enable is changed, eliminating the need for external packages to accomplish a timing delay. Moreover clocked static-input circuitry reduces timing constraints. The memories offer 20-pF clock capacitance and can sink two-to-three TTL loads.
CIRCLE NO. 30 6
1-k bit NMOS shift registers spec 5 MHz
Synertek, 3050 Coronado Dr., Santa Clara, CA 95051. ( 408 ) 241-4300. $4.95 to $11.50 ( 100-999) .
A family of 1024-bit n-channel MOS shift registers provide direct replacements for the AMD 2833 and Signetics 2533 p-channel versions. The new SYP 2533 family uses a 5-V supply, and offers these advantages over the earlier models: no negative power supply required; 50 % less power dissipation; speeds up to 5 MHz. A militarized version-SYM 2833-operates over the temperature range of - 55 to 125 C, and is guaranteed to 2 MHz.
CI RCLE NO. 30 7
F ellow w e know designed a Citizens Band radio for his Volksu.:agon. H e want ed a phone in his bug.

CMOS synthesizer offers 1021 frequencies
Hughes Micro el ectronic Products. 500 Superior A 've., N ewport B each, CA .92663. ( 714 ) 548-0671 . $8.50 ( 1000) .
A CMOS/ LSI digital frequency synthesizer can provide up to 1021 output frequencies from a single crystal. When operated with a 5-V supply, the new HCTR0320 dissipates only 5 mW and accepts input frequencies up to 5 MHz. The circuit consists of an adder/ decoder that accepts a 3-digit BCD num- · ber and a 7-bit binary number; a divider programmable from 3 to 1023; a "Schmitt Trigger" input circuit to condition the input signal to an acceptable t:ounter input, and a phase/ frequency detector to compare the divider output with the external reference frequency.
CI RCLE NO. 308
10-bit CMOS DAC costs $15
Analog D evic es, Route 1 Industrial Park, P.O. Box 280, Noru:ood, MA 02062. ( 617 ) 329-4700.
A monolithic CMOS multiplying d/ a converter features 10-bit accuracy, resolution and linearity, and it costs only $15.00 ( in hundreds ). The DAC operates from a single 5-to-15-V-dc supply and dissipates only 20 mW, including the ladder network. The unit has a differential nonlinearity tempco of 2 ppm of FSR/° C maximum, gainerror tempco of 10 ppm of FSR/° C maximum and operating temperature range of 0 to ·75 C. Output current settles in 500 ns to 0.05 % when the DAC switches all digital inputs low to high or high to low with a 10-V reference.
CIRCLE N O . 3 0 9
ELECTRONIC DESIGN 7, March 29. 1976

You get constant brightness from 4.Sv to 12.Sv - or even 16v.
And that's not all.
Good-by resistors. Good-by brightness fluctuation. Good-by higher loading costs. Good-by bigger inventories. Hello universal lamp. That's what it's all about. The Constant Brightness Lamp (CBL) is a bright new packaging idea from Litronix. The CBL has an IC voltage regulator built into the lamp so the voltage across the lamp doesn't matter so long as it is within a wide range. You can even take the lamp out of one circuit and put it into another. The brightness never varies. Our CBL's operate over three wide voltage ranges between 4.5 and 16 volts. And they plug into any PC board that accepts a Tl or Tl 3A package. Even existing boards. What could be more convenient! Price-wise, they make incredible sense. When you consider you don't have the extra costs for resistors, loading, inventory, and overhead, you can get the convenience of CBL's for about the same installed cost as ordinary lamps.

RLC-200 RLC-201 RLC-210

20 ma@ 4.5-12.5v 10 ma@ 4.5-16v 10 ma@ 4.5-llv

T 1 3A package T 1 3A package Tl package

37¢ in 1000 pc. quantities 37¢ in 1000 pc. quantities 40¢ in 1000 pc. quantities

Get turned on. Ask for details on the new Constant Brightness Lamps from Litronix, Inc., 19000 Homestead Road, Cupertino, Calif. 95014. Phone (408) 257-7910. TWX 910-338-0022.

litronix Nowonder
we'reNo.1 in LEDs
CIRCLE NUMBER 49

PACKAGING & MATERIALS

Plastic-blade stripper handles multiwire cables

Alpha Wir e Corp., 711 Lidgerwood Ave., Elizab eth, N J 07207. ( 201 ) 925-8000. $39.95 with three blade sets (unit qty) .
A new concept in wire stripping, the Alpha plastic-blade stripper, uses blades made of a space-age plastic called Stilan. Its cutting edges are harder than wire insulation, but softer than copper. This allows t he blades to strip insulation from a wire or cable without damage to the conductors and without the need for careful selection of the proper sized notch as with a conventional stripper blade.
The stripper can remove the ins ulation from multiwire cables such as twisted pairs, flat cables and twin-lead antenna wire in - one action without the need to separate t he individual wires, and do it as

quickly as from ordinary hook-up wire.
Alpha claims that time studies show the plastic-blade stripper can operate at least 25 % faster than models using steel blades. The wires being stripped don't have to be carefully positioned between the stripper blades; a number of different wires can be stripped at the

same time; and the stripper requires no adjustment for wire size, type or number of conductors. E ven poorly manufactured wire with off-center conductors is protected against nicks; the plastic blades cut through the insulation, but deform around the condu ctor.
The stripper can handle any size wire from AWG 12 through 28 with almost any type of insulation -PVC cross-linked polyethylene, rubber, neoprene-except T efl on and Kynar.
Stilan is a patented polymer originally developed for aerospace applications. The cutting edges last up to 50,000 strips on simple hookup wire. Replacement injector blades slide easily into place. No tools are needed for replacement.
CIRCLE NO. 301

Q. Is there a recorderjust for spectrum analyzers?

A.

The new 19"rack-mounting SPECTRUM ANALYSIS RECORDER from Raytheon. It's the first dry paper line sca.nni.n.g recorder speciflcally developed.for direct plug-in operation with commerci.aJ.ly available spectrum analyzers.
Any new or existing spectrum analyzer equipped. with the SAR-097 will have a lot more going for it. Likeinfinitelyvariable 100:1 speedrange 5 sec/scanto 50 millisec/scan ... stylus position encoder ... automatic recorder synchronization . . . computer/analyzer compatibility ... high resolution and dynamic range .. .all-electronic drive. And more. If you design andbuild - or buy anduse - spectrum analyzers, you don't have to settle for multipurpose recorders any more. The SAR-097 is here. For full details write the Marketing Manager, Raytheon Company, Ocean Systems Center, Portsmouth, R.I. 02871 . (401) 847-8000.
~AYTHEO~

CIRCLE NUMBER SO

104

ELECTRONIC D ESIGN 7, March 29, 1976

Hand-operated tool cuts and crimps leads
Electronic Production Equi'[Yment Co ., 6 Kane Industrial Dr., H udson, MA 01749. ( 617) 562-9123 . .fi9.50; stock.
A hand tool, the Model 975, is designed to flush out and crimp component leads. It is lightweight, weighing only 5 oz., and measures 5 in. long. The return-spring is double-coil steel and plastic handles are shaped to fit the palm of the hand comfortably.
CIRCLE NO. 320
Mini transistor sockets handle EIA size devices

Garry Manufacturing, 1010 J ers· y A ve., New Brunswick, NJ 08902. (2 01 ) 545-2424. From $0.50; 4 to 6 wks.
Miniature packaging sockets, which will accept standard EIAsize transistors, are available for R0-52, T0-5, T0-18 and in-line transistors, with 3, 4, and 6 pin . Pin circles have either 0.1 or 0.2 in. diameters. The sockets feature closed-entry contacts which resist distortion or damage from mi saligned or over-sized leads. Terminal sleeves are brass and the plating is gold over nickel. Socket terminals for most applications are available: printed circuit, turret, solder-pot, and wrapped-wire.
CIRCLE NO. 321
Solvent disintegrates cured epoxy compounds
Hightemp Resins, Inc., 225 Greenwich A ve. , Stamford, CT 06902. (2 03 ) 325-4124. S ee text.
Hightemp 5625 can disintegrate cured epoxy compounds. It is nonflammable, noncausitic and nonacidic and will not attack metal s. The solvent is available in mini mum 10 lb. containers for $0.75 / lb. and in 45 lb. lots for $0 .69 / lb.
CIRCLE NO . 322
ELECTRONIC D ES IGN 7. March 29, 1976

... Good enough for EDAC's PC Edgeboard Connecto rs, winner of the 1975 Canadian IEEE " Best Component
Design " Award. Why did EDAC choose a TM/ multi-gauge
clad inlay stripe? For some very good reasons :
ECONOMY. It has been a general assumption that clads had to
be at least 100 microinches thick. Not so. TMI provides EDAC with a 30 microinch, 18kt gold alloy , clad inlay on CA725 for their PC edgeboard connector. This results in a substantial savings to EDAC because of the minimal thickness of gold required. The 18kt gold alloy replaces 24kt gold for the contact point providing further gold savings and still meeting rig id performance requirements.
FORMABILITY. TMI clad metals permit the stamping and
forming of complex bends and shapes without any delamination or flaking of the gold alloy.
DUAL GAUGE. TMI dual gauge allows an .025 " thickness for
th e wire wrap post and .012 " for precise leaf spring properties. Dual gauging also permits one source to supply both inlay and dual gauge requirements .
RELIABILITY. The EDAC connector has proven exceptionally
reliable for the two years the product has been in service.
If you're interested in making a good connection , contact TM/ .

.~ .!..!::.. TECHNICAL MATERIALS, INC. ~1

5 Wellington Road , Lincoln . Rhode Island 02865 Telephone : 401 · 728-7200.

_ . . . . . . . . After July 1. 1976. please dial 401 · 333-1700

"'°"

CIRCLE NUMBER 51

105

PACKAGING & MATERIALS

UNBELIEVABLE!!!!!
The lntecolor®8001
A Complete 8 COLOR Intelligent CRT Terminal
$1,995*

"Complete" Means
· 8080 CPU· 25 Lin e x 80 Ch aracter/Line · 4Kx 8 RAM· PROM Software ·Sockets for UV Erasabl e PROM · 19" Shadow Mask Colo r CR Tube · RS232 1/ 0 ·Soc kets for 64 Special Graphics · Selectabl e Baud Rates to
9600 Baud · Sing le Package · 8 Co lor Monito r· ASCII Set ·Keyboard· Bell ·Manual

And you also get the lntecolor ' 8001 9 sector Co nvergence System fo r ease of set up (3-5 min utes) an d stabili ty.
Additional Options Available: ·Ro ll· Add itional RAM to 3 2 K · 48 Lin e x 80 Ch aracters/ Lin e · Ligh t Pens ·Limited Graph ics Mode · Backgrou nd Color · Spec ial Graph ic Ch aracters ·Gam es

*Quan tity 100 (Unit Pri ce $2,495.)

.

®/SC WILL MAKE A BELIEVER OUT OF YOU!

lntelllgent Systems corp 4376 Ridge Gate Drive, Duluth, Georgia 30136

"®

Telephone !404> 449-5961

Conductive grease helps make RFl-tight case
Emerson & Cuming, I nc., Canton, MA 02021. ( 617 ) 828-3300. $4 .70 / lb ( 5 lb and up) ; stock.
Eccosh ield CO is a conductive grease t hat has a volu me resistivity of Jess than 100 0 -cm. It can lubricate metal-to-metal sliding contact areas, which require continuous electrical conductive paths. T he grease can also ground enclosures, which require lubrication to overcome friction as well as electromagnetic-interference co ntrol and rf caulk metal-to-metal joints. P roper shield design and use of Eccosh ield CO can produce insertion loss valu es of 100 dB .
CIRCLE NO. 323
Heavy-duty connectors meet MIL-C-22992E

CIRCLE NUMBER 52

When it comes to value...

ENI Model 320L Amplifier

AR Model 30LA
:---- Amplifier
0

Model 30LA is a HEAVYWEIGHT
Feature-for-feature, the Amplifier Research Model 30LA
broadband ampIifier outweighs the EN I 320 L. Th is rugged,
high performance ampl ifier provides a minimum 30-watt output from 1-110 MHz. It offers a directional power meter, adjustable gain control , infinite mismatch tolerance, and low harmonic distortion.

If your considering an ENI 320L or any other ENI amplifier, send us the model number. We'll provide you with specifications on a competitive unit.
181.· RIDPLIFllR Amplifier Research 160 School House Road
. . . . Rl!SBARDI Soudenon , Pa. 18964
YOUR BEST SOURCE FOR RF POWER AMPLIFIERS

Amphenol Connect or, 2801 S . 25th
A ve ., Broadview, IL 60153. ( 31 2)
261 -2000. F or 100-up quanti ties:
$100 ( mated pair) ; s'tock.
A line of mult icontact, heavyduty, waterp roof plu g and receptacle connectors is fully qualified to latest specifications of MIL-C22992E, Class L . Shell siz,e 28, 32, 44 and 52 connectors, with current rat ings of 40, 60, 100, and 200 A, respectively, are in it ially avai lable. The power distribution connectors offer several significant features : An arc-suppression ch amber within t he connector protects users from serious shock hazards, an internal multiple-part environmental sealing mecha n ism completely waterproofs the assemblies, wheth er mated or unmated, a builtin five key shell polarization prevents mismatings and an integral safety ground is included in compliance with requ irements of OSH A and t he National E lectrical Code for grounding connectors.

CIRCLE NUMBER 53

CIRCLE NO . 324

106

ELECTRON IC D ESIGN 7, March 29, 1976

Superior performance... Significant cost advantages... Off-the-shelf delivery.

;;
l
~

! ~ !sooo ·· l 31,0

80 0,9

60 0,6

40 0.4

20 0,2

9904 120 12601

100

current

Miniature ironless rotor DC motors. Ideal for cassette drives.
The typical performance graph shown above spea ks for itself. C.1r miniature ironl ess rotor 12 VOC motors not onl y have the desired characteri sti cs for cassette drives, they also offer an important pri ce advantage-under $10.00 in 500-piece lots. As low as, if not lower than , any competit ive motor. Fast, off-the-shelf deliveri es, too!
Motor time constant is 23 MS ; rotor torque SO gem; starting torque 230 gem . Plus, low noise levels and smooth cog-free operation . The motor can also be ordered w ith double shaft for use as a tach motor. 24 VOC models also avail able.
Send for information today!
I I A.W. HAYDON CO . PRODUCTS NORTH AMERICAN PHILIPS CONTROLS CORP.
Cheshire, Conn. 06410 · (203) 272-0301
CIRCLE NUMBER 54

BENCHMASTER··· eeeA 5 CUBIC FEET OF BENCH-TOP TEST SPACE!
Economical, portable, and compact, this all-new frontopening temperature and humidity test chamber is only 4 feet wide!
It's extremely versatile, too. Benchmaster offers medium or extreme temperature ranges-with or without humidity.
Benchmaster is available in 4 performance variations: Model BTH: 0°F to 200°F with humidity Model BTRS: -30°F to 350 °F with humidity Model BTR: -100°F to 350°F with humidity Model BTC: -100°Fto 350°F without humidity
Write for complete information.
~ -~l!.!!llft.¥
1090 Springfield Rd., Union, N.J. 070B3· (201) 686-7870·(212) 962-0332
CIRCLE NUMBER 55
ELECTRON IC D ES IGN 7, March 29, 1976

There GoesYour Reputation --Up In Smoke.

Here's how to protect ·compact - diameter, your product, your cus- .157" ; length, .457" (extomer-and yourself! elusive of leads)

Just add MICROTEMP ' ·economical - priced as safety thermal cutoffs low as 9ci:

to your plans. The millions · proved reliable in millions
already in use a.r .e your of on-the-job applications
assurance of PC?S1t1ve , yet · installation ease -
lowcostprotect1on aga1nst assorted terminations
overheating .caused. by mounting packages and ' malfunctions 1n electrical insulations are available c1rcu1ts and components .

MICROTEMP is a reliable ,
accurate. easy to install, " one shot" thermal limiter.
Because of its patented desi~n and construction , it wont derate . And , it's
unaffected by age o r
extended use.

Recognized under the
Component Program of Underwriters' Laboratories, Inc. UL File #E40667A.
CSA and BSI Certificate
#5041 approved. Recognized by MITI and VOE . Military approval.

Compare this data:

· wening tolerance -

0
: ter:perature range -

~

58 to242 ° C.C136

to468 °~

For additional information, check the reader service card, or call or write:
'·'·' MICRO DEVICEScoRP. 1881 Southtown Blvd ., Dayton , Ohio 45439 Ph : (513) 294-0581 Telex : 28-8087
CIRCLE NUMBER 56
10 7

MODULES & SUBASSEMBLIES
Drive lines and discriminate pulses at 50-MHz data rates

Tau-Tron, 11 Esquire Rd., North
Billerica, MA 01862. ( 617) 667-
3874. P&A: See text.
High-speed comparators and line drivers for automatic test equipment have been introduced by TauTron. These units can operate at frequencies of over 50 MHz and are avaifable in either printed-circuit mountable modules or complete PCcard assemblies.
The analog-comparator module, the M-AD-10, is a 1 x 1-in. hybrid circuit that can operate as either two independent single-level discriminators or as a dual-level unit. Each input can handle a maximum differential voltage of ±5 V, and has a maximum common input voltage of ± 3.5 V. The input resistance for either input is 6 kn, and the differential input offset voltage
is ±2.5 mV at 100 n. An error
band of ± 2 mV is added by the comparator to the input signal.
Inputs of the M-AD-10 are in-

tended for ECL-level signals, as are the outputs. However, the outputs have open-emitter transistors that require external termination.
When operated as two independent comparators, each discriminator has its own threshold adjustment. In the two-level mode, the two data inputs are tied together and the trip points can be set using separate threshold adjusts. Each discriminator also contains a latch that either permits the reference voltage to be compared normally with the input signal, or Jocks the discriminator output to the existing state of the data.
Switching times are fast-the input-to-output, high-to-low transition, for instance is 10 ns. Latchenable times are also 10 ns, and the time the strobe line requires to move data to the output is a mere 1 ns.
The discriminator module offers four usabli:: outputs- a channel-1
,SORRY! rr5~,, 1 SAV~ MONE ·
8UT HE.RE AR
iWO 1iCKET5 TO lf-/E t.ODI STRAY
~CATCHING-
RODEO·

high output, a channel-!:: low output, a gray region output and a discriminator-valid output. The gray-region output lets you know when the voltage levels present at the input lines are somewhere between the low and high limits. The discriminator-valid line is the complement of the gray-region line.
The line-driver module, the PM50, is a programmable power amplifier that operates at frequencies of better than 50 MHz. It has individual control of input and outputpulse top and input and outputpulse bottom and measures only 1.25 x 2 in. The input is designed for ECL-level signals and is termi-
nated by 50 n to - 2 V. (50 n to
ground is available as an option. ) Both the input and output pulse
tops and bottoms can be adjusted over a ±2-V range, although ±5V adjustment ranges are available on the outputs as an option. The amplifier has an input impedance of 10 kn and will reproduce the original input signal to within ± 20 mV. Rise and fall times for the amplifier are 2 ns, typically, with the total propagation delay reaching only 7 ns.
Signal aberrations on rising or falling edges are guaranteed to be no more than 100 mV pk-pk or 7 percent (whichever is greater ) when the module is properly terminated. Output terminations mu st be specified when the module is ordered, and can be any valu e between 50 and 100 n.
Prices for the modules start at $350 for the M-AD-10 di scri minators and reach $450 for the amplifier module. Circuit cards with the modules built in range from $400 to $585. The cards measure 2.5 X 5 in. Modules and cards are avai lable from stock.

CIRCLE NO . 304

AN~L.O

I

L,Jou CANT I.OSI: WITH 1HE:: WOK'L.DS FIRST MONOLIT!-llC 14-PIN DIPWFN CON~Fl.TER.

E.)(TERNAL R'tC DE'FINES PROPoR1lONAL

FULL SCALE. f=REQUENCY OUIPUT

(T'TL DTL CMOS COMPATIBLE) "THROUGH

THE .100' Kl-42 BAND. 0. 05% LINEARITY

~(Ot.0'2A5E-%sIN+@PoU1oT0AOS1FA<HoF2-/)vroFF+OO~~JOAFUV2-.L-LWU5IREE

iAIA L.INK OR' COMBINE II WITH

A BINARY COUNTER FOR ND

i:;.NCODll'lG RATE: OF 25 /2-BtT

CONVEF?SIONS I SEC:.

I···;·ntech/PMI .

.

1CA9q2~oBsoRO(4KoASW) 2R.4O4.

SANTA CLMI,
. osoo

108

CIRCLE NUMBER 57

ELECTRON IC D ESIGN 7. March 29. 197 6

Improved acquisition modules cut costs
Data Translation, 109 Concord St., Framingham, MA 01701. ( 617) 879-3595. See text; 4 wki.
The DATAX II series of modular data-acquisition systems offers improved specs at lower prices than the company's older DATAX I series. Models DT5720 and DT5740 offer 12-bit resolution and throughput speeds of 50 and 25 kHz at prices of $575 and $475, respectively. The modules have threestate outputs, which permit their use with most microcomputer systems. Linearity of the DATAX II series is ± 0.5 LSB over 0 to 70 C and the systems have an accuracy of 0.03 % for the full-scale range. All units are housed in 3 x 4.6 x 0.375 in. metal modules.
CIRCLE NO. 325
Multiplying d/a accepts 13-bit input words

B eckman Instruments, H elipot Div., 2500 Harbor Blvd., Fullerton, CA 92634. ( 714) 871-4848. From $100 ( 100-up) ; stock.
The 877-69 series of multiplying d/ a converters includes units with resolution of up to 13 bits. They have provisions for external ac or de references for full four-quadrant operation, can handle ru:: reference frequencies from de to 10 kHz, and have an MSB inversion input for TWO's complement or offset binary arithmetic options. The 30-pin, dual in-line metal or ceramic packaged devices are available in two accuracy (linearity and gain) code models. Typical ac· curacy of Model 877-69M-Dl (metal package ) is ±0.012 % at 25 C, guaranteed to ±0.025 % over - 55 to + 125 C, or ± 0.05 % at 25 C guaranteed to 0.1 % for Model 877-69MD2. Typical accuracy of Model 877-69C-Cl (ceramic package) is ± 0.012 % at 25 C guaranteed to ±0.025 % over -25 to +85 C or ± 0.05 % at 25 C guaranteed to ± 0.1 % for Model 877-69C-D2.
CIRCLE NO. 326
ELECTRONIC DESIGN 7, March 29, 1976

CIRCLE NUMBER 58
99 and 44/100% reliable.

..

Our return rate on encapsulated power supplies is less than 1% . This excellent reliability is one of the reasons we ' re the world ' s leading manufacturer of encapsulated power supplies.
Like to hear more reasons? All our power supplies feature internal short circuit protection . All are "tripletested" before delivery to insure performance . And all have a 24 month warranty. We offer 49 models with single and dual outputs from

3.6V to 28V, and with output currents from 65mA to 2000mA .
Best of all , the cost is surprisingly low, and delivery is extremely fast .
Want to find out more about our power supplies? Simply circle our number on the Reader Service Card and we ' ll mail you our new Power Supply Catalog . If
l . you're in a hurry, call us at
(305) 974-5500 .
~ ComputerProdurt-.lnc.

!
:I
'°""""'""n·m·"'"'"'"""""°'"" a. O·M··Oo·· 0 1400 N.W. 70th Street . Fort Lauderdale , Florida 33309 · (305)974-5500. TWX (510) 956-9895 «e-l CIRCLE NUMBER 59 109

We're sti

Stephen J. Scorza General Manager NOBEL ELECTRONICS, INC.
Tell us what you think about the GOLD BOOK. (If it's good, we'd like to hear it. If it's bad, we want to improve it.)
11 0

--
EL ECTRONI C D ESIGN 7. March 29. 1976

getting business from ~rmyn's catalog pages
in the GOLD BOOK
"We receive numerous calls and letters, both from the U.S.A. and all over the world, which we can readily ascribe to the GOLD BOOK,'' writes Stephen J. Scorza, General Manager, Nobel Electronics, Inc., New City, New York.
In July 1975, Nobel assumed U.S. stocking, marketing, and sales operations for Jermyn, an English company. (Jermyn manufactures semiconductor hardwar!3: IC and transistor sockets, mounting pads, transi-pads, insulators, and heat sinks.)
"Many of the engineers who contact us refer to specific Jermyn products illustrated in the GOLD BOOK, requiring either the standard item or a slightly modified version. A brief phone conversation, followed-up with evaluation samples, is frequently all that is needed to produce the initial order. Now, that's cost-effective selling-and all because the catalog pages serve to qualify readers, making them much stronger prospects.
"The GOLD BOOK is a good selling tool because it is an extremely good buying tool. We use it ourselves to locate new sources of old items and to discover new items that may be useful in design and test."
Because the GOLD BOOK goes primarily to Electronic Design's audience of specifiers, Jermyn (and now Nobel Electronics) gets the benefit of 78,000 engineers, engineering managers, purchasing agents and distributors throughout the U.S.A., not to mention 13,000 overseas. These are the men who are ready to talk business-the men who have the authority to buy.
ELECTRONIC DESIGN'S GOLD BOOK IS WORKING ···IT'S WORKING FOR READERS···AND IT'S
WORKING FOR ADVERTISERS, TOO.

ELECTRON IC D ES IGN 7. March 29. 1976

111

DISCRETE SEMICONDUCTORS

Varactor tuning diodes have Qs of 12,000

10 & 15-A transistors switch · fast and have high gain

Alpha Industri es, 20 Sylva,n Rd., Woburn, MA 01801. ( 617 ) 9355150. $75 to $98 ( small qty .); 15 days.
The DVE4550 series of gallium arsenide tuning varactors has wide tuning_ ratios and high values of Q. A choice of five standard ceramic/ metal packages is available. All diodes are burned-in prior to final measurement. Some of the diode charac.teristics (when measured at 25 V and 10 ,µ,A ) include: capacitance range, 0.4 to 4 pF; Q_, range (at 50 MHz ), 4300 to 12,000; Q_4 range (at 1 GHz ), 215 to 600; and reverse leakage current at 20 V bias, 100 nA.
CIRCLE NO. 327

LED lamps come in many colors

Gen eral S emiconductor Industries, 2001 W. T enth Pl., T empe, AZ 85281. ( 602) 968-3101. S ee t ext; up to 1000 pieces avaiLable from stock.
The first 10 and 15-A power transistors that have total switching times of less than 1 ,µ,s are available from General Semiconductor Industries. Their de-current gains are at least 10-a figure most other manufacturers require Darlington configurations to get, and then only at slower speeds.
Of the discrete transistors already on the market, the one that comes closest is the SVT 400-12 from TRW Power Semiconductors (Lawndale, CA). It is a 12-A, 400V device with a maximum rise time of 0.5 ,µ,s, a maximum storage time of 2 µs, and a maximum fall time of 0.5 .µs. Its dc-eurrent gain is at least 10.
In comparison, the XGSR15040 from General Semiconductor is a 15-A, 400-V device that has a maximum rise time of 0.07 ,µ,s, a maximum storage time of 0.35 µs and a maximum fall time of 0.2 .µs.
112

Minimum de current gain is also 10. There are also 250.. ·.QOQ and 350-V versions with the same switching speeds but minimum gains of 20, 15 and 10, respectively.
General Semiconductor's 10-A device has the same gains at 250, 300 and 350-V as the equivalent 15-A versions and are just as fast.
These General Semiconductor transistors all come in a standard T0-3 package. The allowable junction temperature for the transistors
ranges from - 65 to + 175 C.
Saturation volitage on all of the General Semiconductor devices is no higher than 0.8 V.
Costs, in 100-999 quantities, for the 15-A transistor start at $14.75 for the 250-V unit and increase to $20 for the 400-V unit. 10-A device pricing ranges from $13 for the 250-V unit to $14.25 for the 350-V unit.
TRW's transistors cost $8 to $9 for 100-piece lots. General Semiconductor

TRW

CIRCLE NO. 302 CIRCLE NO. 303

H ewlett-Packard, 1501 Page Mill Rd., Palo Alto, CA 94304. ( 415 J 493-1501. $0.19 to $.65 (100-999 ) .
Four new low-cost LEDs in a radial-lead subminiature epoxy package include a red, yellow, green and a high-efficiency red type. They can be mounted in stacked arrays on 2.21-mm centers for high-density applications. A tinted d~ffused Jens for each color provides high on-off contrast with a wide viewing angle. At a forward current of 10 mA, the red HP 5082-4100 has an axial luminous intensity of 0.7 med; the red HP 5082-4101, 1 med. Forward voltage is 1.6 V. The high efficiency red has an output of 3 med at a forward current of 10 mA and forward voltage of 2.2 V.
CIRCLE NO. 328
ELECTRONIC DESIGN 7, March 29, 1976

Behind eyery
pod designer

· I

·

1Sane.v

Cantbion catalog.

Our new giant 747-A general catalog has a 56-page section just on new products introduced since our last big catalog. That 's in addition to our familiar products like solder terminals, terminal boards, insulated terminals, coil forms, coils, RF Chokes, connectors, capacitors, IC accessories, hardware and thermoelectrics. You can get one behind you free just by writing: Cambridge Thermionic Corporation, 401 Concord Ave., Cambridge, MA 02138.

Standardize on
~-0#®
The Guaranteed Electronic Components
CIRCLE NUMBER 61
Facts. The GOULD/Brush 2400 delivers more of them with
less fuss, bother and cost than any Other oscillograph
you can buy.
And it does it on a wide 1OOmm channel and at a remarkable 30Hz. Available in 2, 3 and 4 channel models with all the Gould exclusives, of course.
For the full Gould 2400 story, write Gould Inc ., Instrument Systems Division, 3631 Perkins Avenue, Cleveland, Ohio 44114. Or Gould Allco S.A. , 57 rue St. Sauveur, 91160 Ballainvilliers, France.
PHONE FREE (800) 648-4990 FOR BROCHURE.

CIRCLE NUMBER 62
ELECTRONIC D ES IGN 7. March 29, 19 76

FOR DATA CIRCLE NUMBER 271 FOR DEMONSTRATION CIRCLE NUMBER 272

DISCRETE SEMICONDUCTORS
Microwave transistors have 1.7 dB of noise

Voltage crowbars handle Improved opto-isolator 3 to 235 A continuous replaces earlier version

------·6

· 2.---+--"
3----+-

----5
~--4

Fujitsu Limited, Syuwaonarimon Building, 1-1 Shinbashi, 6-Chome, Minato-ku, Tokyo 105, Japan .
A microwave low-noi se transistor, the F J203, has noi se characteristics of 1 dB at 1 GHz and 1.7 dB at 2 GHz. The transistor is passivated with s ili con-nitride film and is housed in a metal/ceramic hermetic package. Specifications of the transistors include: a gainbandwidth product, fT, of 8 GHz ; a maximum available power gain of 13 dB at f = 2 GHz; and a power dissipation of 200 mW,· max.
CIRCLE NO. 329

MCG, 297 Skidmore Rd., D eer Park, NY 11729. (516 ) 586-5125. From $3 ( 1000-up ); 2 wks.
The Series LVC-1 de crowbars switch in less than 10 µs from an open to a vi rtual short circu it. Potentially destructi ve energy from transients, series regulator faults, mi sadju stments, etc., can be almost eliminated. The crowbars recover when power is momentarily removed. Trip voltages are available from 4.7 to 600 V de at current levels ranging from 3 to 235 A de. T emperature range is - 55 to 100
c.
CIRCLE NO. 330

Energy Electronic Products, 6060 Manch ester A ve., Los Angel es, CA 90045 . (213) 670-1275 . $0.89 ( 100up); stock.
The EL 74 A opto-isolator comes in the same six-pin plastic DIP as the EL 74, whi ch it is replacing. The improved unit has a response time of 2 µ,s compared with 20 µ s for the old ; a dark current of 50 nA instead of 500 nA; and a breakdown voltage of 30 V instead of 20 V. Current transfer ratio, isolation voltage and isolation resistance are the same as for the older units (35 %, 1500 V, and 100 Gn, respectively).
CIRCLE NO. 331

Power totheµP

Sola offers DUAL and TRIPLE OUTPUT POWER SUPPLIES for MICROPROCESSORS and accessories: RAM's, PROM's, ROM's, FPROM's, CLOCKS and 10 devices.
All available from your local electronic distributor. At competitive pricing. From a name you can count on-Sola.
Our versatile power supplies offer fully isolated independent outputs for either positive or negative operation. Series or parallel operation . Plus, remote sensing/ programming, and complete serviceability. Just call or write for Catalog 647.
For added protection, consider our minicomputer regulators, UPS, and Standby units. Everything you need for MPU power and protection.
Sola Electric, 1717 Busse Road, Elk Grove Village, Ill. 60007 (312) 439-2800 .

SOLA ELECTRIC
BOLA BABIC

Think of us as your supply line.

CIRCLE NUMBER 64

114

ELECTRONIC D ESIGN 7, March 29, 1976

DATA PROCESSING
Disc storage multiplexed among four processors
Wang L a boratories, I nc., 83 6 North St., T ewksbury, MA 01876. ( 61 7) 851-4111. $800: first units, $500: each of three additional; 2 wks.
Disc-storage units a re one of the most expensive elements of any data-processi ng system, according to Wang. With its new Model 2230MX-A/ B disc multiplexer, a user can cut this cost. The multiplexer allows up to four System 2200 processors to share a si ngle di sc drive. Access is on a " daisy-chain" basis, with a master controller polling each processor sequential ly on an equal-priority basis. All processors sharing the disc have almost concurrent access at all times, si nce a si ngle access typically requires from 20 to 80 ms to complete.
CIRCLE NO. 332
PROM eraser delivers calibrated UV dose

The Fastest wau:
Data Acquisition with 11c.
Throughput rates of 125KHz or 8 µ.seconds per channel are now easily accomplished with our DT5710A Data Acquisition Module. Our second-generation DATAX IITM Data Acquisition Module is complete with multiplexer, differential amplifier, sample/hold, 12-bit A/D converter, and all control and programming logic ... plus TRI-STATE outputs for direct connection to computer busses.
A fast data acquisition front end solves the throughput problem in µ.C systems where time is at a premium. OMA systems, FFTs, telecommunications, and large multi-channel systems can also benefit from the DT5710A's throughput of 125,000 channels per second.
Call us at 617/879-3595 for a complete set of applications data.

JIC

DATA TRANSLATION

. . . . .~lllllllllllllllllllmli!l~~~INC
109 CONCORD ST., FRAMINGHAM. MA 01701 (617) 879-3595

TELEX 94-8474

"" CHESBRETT FMH '"

CIRCLE NUMBER 65

Turner D esigns, 2247A Old Middlefield Way, Mountain View, CA 94043. ( 415 ) 965-9800. $295 (unit qty ).
The Model 30-000 PROM eraser can deliver the correct UV wavelength and intensity for MM5203Q, 1702A, 2708 and similar type PROMs, and handle as many as 60 si multaneously. Devices are loaded with removable metal trays, which protect the PROMs against electrostatic damage. Operation is controlled by an adjustable timer, cali brated in increments of 1 min. Exposures can be set from very short durations to more than 1 h. Lamp start is automatic. The operator is protected from UV exposure by a door interlock and from ooone by a specially designed lamp envelope.
CIRCLE NO. 333
ELECTRON IC D ESIGN 7, March 29, 1976

A New High in Stability
Centre Engineering has met the challenge of providing ultra-high reliable sub-mi nature ceramic capacitors for the space programs. Now, design engineers in the tele-communications, computer and instrumentation industries can have ceramic capacitors in high volume for low cost applications, using the same processes and manufacturing techniques from Centre Engineering .
Ceramic capacitors are available in 40 various formulations with a capacity range of 1pf to 1Omfd . For applications requiring large vo~ ume , low cost ceramic capacitors consider Centre Engineering. Catalog available upon request.
h- CENTRE ENGINEERING 2820 E. COLLEGE AVE. , STATE COLLEGE. PA. 16801 814-237-0321 ·TWX 51C>-691-2634
CIRCLE NUMBER 66
11 5

Free

Ca
a

DATA PROCESSING

· ·

2400 lpm printer sells for $3000

Use Power/Mate power supplies. We'll same day.

save you time and money because we make

Power I Mate's bui Iding block approach

more power supplies for more applications even enables you to design customized

than any other power supply manufacturer power supply systems from off the shelf

in the business.

units.

And that's not all . We'll service you

And everything we sell is unconditionally

from stock with whatever you need for

guaranteed. Gall or write for our 84 page

whatever the job and usually ship it out the catalog today .

1~1rn1~1
POWER/MATE CORR
World 's largest manufacturer of quality power supplies. 514 South River Street/ Hackensack, N .J. 07601 /Phone (201 ).343-6294 TWX 710-990-5023

CIRCLE NUMBER 68

AUTHOR'S GUIDE

writing for
Electronic Design

An

Author's

/·~
' ~~"·~.r(f
..,/'"'\I .J~ _J

Guide

~\· ~~c1V>\
~ IJl~~ -----

If you 've solved a tricky design problem, if you have developed special expertise in a specific area , if you have information that will aid the design process .. . share it with your fellow engineerreaders of Electronic Design.
Art ic les you have authored not only raise your own professional status, but help build your company image as well . The readers benefit, your company benefits.
To help you prepare material that meets Electronic Design 's high editorial standards, our editors have prepared a special author's guide entitled " Writing for Electronic Design/ It covers criteria for acceptability, form, length, writing tips, illustrations, and payment for articles published . It's available without cost.
It's easy to write for Electronic Design, but it's often hard to get started . Send for your copy of our Author's Guide today .
Circle No.
895

116

Houston Inst?ument, One Houston Square, 8500 Cameron Rd., Austin, TX 78753. ( 512 ) 837-2820. S ee text.
A 2400 line/ min printer, Model 8210, sells for only $3000. Its output is 80-columns wide on 8-1 / 2in. paper. Also a 132-column output, which prints on 14-7/ 8-in . paper at 1400 lines / min sells for $3785. Their features and performance rival that of $10,000-to-$20,000 printers, according to the manufacturer. The features include a full-print line-buffer memory, automatic top-of-form advance, 400-in/ min paper-advance speeds, the ability to use both roll and fanfold pape1· interchangeably, and enough speed to make the printer capable of doing a core dump from a 64 kbyte mini in less than 30 s. Lowcost electrostatic . printer paper commonly available is used.
CIRCLE NO . 334
Core memory designed for microcompu'ters
Ampex Corp., P.O. Box 33, Marina d el R ey, CA 90291 . (213 ) 821-8933. $99.95 (OEM qty) .
The MCM-4300 is the second in Ampex' family of microcomputer core memories designed for terminal, peripheral and microprocessor applications. The memory provides a nonvolatile storage of 2048, 1024, 512 or 256 four-bit data words. Applicable to read/ modify/ write applications, the memory modules provide data access in 450 ns. Only a single uncompensated 5-V power sou rce is required. 'Each module includes timing and control, data and address registers, decoding and drive circuits and a TTL-negativetrue interface. Multiple modules may be combined in parallel for larger capacities.
CIRCLE NO. 335
ELECTRONIC D ESIGN 7, Maroh 29, 1976

Thick Film Dual-In-Line Resistor Networks
· Resistor Values: 100 ohm to 10K ohm · Tolerance: ± 2% · TCR: ± 200 ppm/°C · Package Power Rating : 2.5 watt · Four popular series: MEC1, 13 resistor, 14 pin MEC3, 8 resistor, 16 pin MEC2, 7 resistor, 14 pin MEC4, 15 resistor, 16 pin

Now Available For Off-The-Shelf Delivery From Centralab Distributors

Not just another resistor network, these are backed by Centralab's 31 years in thick film microcircuitry. They're proven in use ... reliable .. . for such typical applications as pull-up and pull-down networks or line terminators. Best of all you can get them fast . .. through our network of over 200 Centralab Distributors. When you think of networks-think of Centralab. Call your Distributor for complete details, prices and delivery.

DISTRIBUTOR PRODUCTS
- - ·..-~ --~
~
CENTRALAB
Electronics Division GLOBE-UNION INC . 5757 NORTH GREEN BAY AVENUE MILWAUKEE . WISCONSIN 53201

CIRCLE NUMBER 69
Rose New. BeautUul. Quality. Standards.

Rose Enclosures, made specitically for electronic

use, culminate years of design, engineering and

production experience. Extra high quality, preci-

sion-finished units provide functional protection.

easy access. excellent esthetics. Available mate-

rials: Lexan. Aluminum. Polyester and ABS. Clear

plastic covers with Lexan and ABS. A competi-

5EJi tively-priced stock of Rose Enclosures is main-

tained in Belding. Mich. for immediate

~a 'UT 'ftt..T ~ &AA&d&t

shipment. Contact us at ( 616) 794-0700.

BFOTHERS ll'JC
Belding. Michigan 4aao9

CIRCLE NUMBER 70
ELECTRON IC D ESIGN 7. March 29. 1976

RAPID IC INSERTER FROM 'MES' WILL PAY FOR ITSELF WITH INCREASED PRODUCTION.
STICK-A-DIP the first, truly new innovation in manual insertion tools in years. Accepts plastic shipping stick. Eliminates handling of ICs. Uses either 14 or 16 pin ICs mixed. Squeeze trigger until IC leads protrude from nozzle, align into respective holes in printed circuit board and squeeze trigger again, IC ejects into PCB.
STICK-A-DIP is jam-proof, lightweight, projected nozzle for easy alignment. DIP-STICKS permit pre-pro-
gramming for production and inventory control. ----; STICK-A-DIP #1100. DIP-STICKS #P/N 1101.
, .mi1:ra Eledrani1: Systems ln1:.
'--~- 8 KEVIN DRIVE, DANBURY, CT 06810 TEL (203) 746-2525
CIRCLE NUMBER 71
11 7

SOMETIMES OUR STANDARD
POWER SUPPLIES
ARE A LITTLE SPECIAL I
For special electrical and/or mechanical power supply needs , Arnold Magnetics is hard to beat. Our unique modular concept allows us to mix our standard modules with specials to meet custom design requirements. The result is reduced engineering costs, fast deliveries and proven performance . And with over 1200 possible standard configurations a special from someone else may be just another standard for us. · Single or dual inputs:
115 VAC , 47-500 Hz.
12. 18, 48, 115, 150 voe.
· Multiple isolated and regulated DC outputs
from 4.2 to 300 voe.
· Line & load regulation to 0.1 %. · Up to 400 watts per output. · Efficiencies to 85%. · Completed units provided in tested and
encapsulated , conduction cooled packages . Call or write for more information today!
·1·'
ARNOLD MAGNETICS CORPORATION
11520 W. Jefferson Blvd . Culver City , Ca. 90230 · (213) 870-7014
CIRCLE NUMBER 72 118

COMPONENTS
Sensitive relays come in low-profile package
Gould Inc., Allied Control Div ., 100 Relciy Rd., Plantsville, CT 06479. ( 203 ) 628-9654. From $3 .1 5 ( 1 to 24) ; stock.
The MPCS relays have a 160 mW sensitivity at pull-in. They arc available in either a 1-form-C or 2-form-C contact configuration. Either configuration can switch 2 A. The relays are also low-profile units-only 0.415 in. hi gh X 0.6 wide x 1.1 in. long.
CIRCLE NO. 336
Lead-oxide vidicons offer users many plusses

Narrow thumbwheel swi'tches cut panel space
Cherry Electrical Products, 3600 Sunset Ave., Wauk egan, IL 60085. (312) 689-7702. $2.15 (2000-up) ; stock.
A 0.35-in.-wide thumbwheel . switch series, the T35, has 0.16-in.high dial characters. The T35-02A comes in a black-gloss finish and has BCD outputs. The T35 series thumbwheels may be ordered individually or in assemblies of several switches ganged side-by-side. An assembly of 40 switches com-
plete with end caps, uses only 1 x
12 in. of front-panel space.
CIRCLE NO. 338

English Electric Val ve North America Ltd., 1 America Dr., Cheektowage, NY 14225. (716 ) 632-5871. $1925 to $2200 ea.; stock.
The P8130 series of Leddicon ( lead-oxide vidicon) TV camera tubes has five advantages over typical vidicons. Because of its coaxial construction it offers: separate or integral mesh operation, reduced line-scan pickup, operation at any attitude, self-generated or variable-light bias that results in low lag and good dynamic resolution with uniform dark current, and use in virtually any 30-mmdiameter camera. The tubes fit standard, unmodified, 30-mm sockets (such as type 56021 ) and require a total current of 300 mA for energizing the cathode heater and internal light bias source. The heater voltage of the tu.be is 6.3 V ±5 %, the ratio of capacitance of the signal electrode to that of all other electrodes is 3 pF to 6 pF and the peak spectral response is approximately 500 nm.
CIRCLE NO. 337

Bleep to blast with this sound kit
C.A. Briggs, Co., P.O. Box 151, Glenside, PA 1901'18 . ( 215 ) 8852244. $34.95 (unit qty ) ; stock.
The new Cybersonic designer's kit makes it possible for the designer to listen to and demonstrate a bleep to a blast range of sounds. The 14 sounds that can be produced from the devices and accessories included in the kit provide nominal sound-pressure levels of 65 to 90 dBA at distances of 3 to 10 ft. Current drain is in the range of 3 to 30 mA at the nominal-operating voltage of 12 V de.
CIRCLE NO . 339
ELECTRONIC DESIGN 7, March 29, 1976

6th international exhibition
MESUCORA76
Measure · Analysis · Control · Testing · Automation

551 groups of Measurement, Analysis, Control, Regulation and Automation instruments form in
Paris a
unique confrontation
between the 900 best well-known manufacturers from 23 Countries. 400 French, 500 Foreign Companies covering the various techniques
Acoustic, Automation, Chromatic, Electronic, Electrotechnic, Flow Control, Computing, Magnetic, Nucleonic, Optic;, Pneumatic, Therm ic
CIRCLE NUMBER 73

10th.17th JUNE 76- PARIS
Pare des Expositions Porte de Versailles (France)
Full information for: FRENCH TRADE SHOWS-French Chamber of Commerce in The United States Inc. 1350 Avenue of the Americas NEW YORK N.Y. 10019 TEL: (212) 582-4960

LOOKING FOR
A
DISTRIBUTOR
NEAR YOU?
Electronic Design's GOLD BOOK lists 5, 700 distributors with access both alphabetic, by distributor name, and geographic by location.
When you need information ...
Electronic Design 's
GOLD BOOK
IS THE PLACE TO LOOK

NEED ACOMPETITIVE EDGE?
CHECK OUT
WESTON· POTS
FOR COST DELIVERY · PERFORMANCE
EXAMPLE: Model #830P WESTON RECTILINEAR %"CERMET TRIMMER PRJCEoooo Piece Orders~ .91EA.

E LECTRON IC D ES IGN 7, Ma rc h 29. 19 76

CIRCLE NUMBER 74
119

INSTRUMENTATION
Charge amplifier works over wide range
~rr-:='.-!=..·:~i -·
Kristal Instrument, 2 4 7 5 Grand Island Blvd., Grand Island, NY 14072. (716 ) 773-4150. From $300 to $975; stock to 2 wks.
Charge amplifier, type 5003, and range selector, type 5423, convert electrical charge signals (100 to 106 pC) from piezoelectric transducers into proportional voltages for direct reading on a scope or other indicating instrument. The amplifier comes with three, six or nine ranges, which can be set manually or, optionally, by remote control. Fine adjustment of the individual range is also possible to calibrate the amplifier for a specific transducer.
CIRCLE NO . 340
High-voltage pulser sells for $965
Instrument Research Company, P.O. Box 231, Lincoln, MA 01773 . ( 617 ) 897-7647. $965; 30 days.
Model 941 power pu lse generator is pdoed below $1000. Featuring an output adjustable to 2 kV at load currents to 1 A, the new unit maintains a clean pulse into an essentially capacitive load. The driver features complementary TTL outputs together with an independent ± 30-V offset and amplitude capability-a combination which permits driving all logic families directly. The 941 thereby offers four simultaneous outputs together with five modes of operation-single shot, triggered, gates, delayed and normal PRF.
CIRCLE NO. 34 1
120

Analog VOMs, move over! Here's a pocket DVM
Se-rwore, Inc., 3200 Sencore Dr., Sioux Falls, SD 57107 . ( 605 ) 3390100. $124.
Pocket-portable DVM35 takes aim a:t portable analog VOMs. The unit features three-digit readout, 1 % de voltage accuracy, coupled with 15-MO input impedance. Capabil ities include 1-A and 10-M!.1
measurements plus 2000 v de with
a "times two" button on the probe thart doubles all voltage ranges for expanded field use, plus increases the input impedance to 30 MO. DVM35 weighs only 1 lb with AAsize batteries. It is said to be "dropproof" and "burn-out-proof."
CIRCLE NO. 342
Sweep generator carries low price tag
Wavetek Indiana, 66 N . 1st Ave., Beech Grove, IN 46107. (317 ) 7833221. $495; 30 days.
Model 1050A sweeper sells for less than $500. The broadband instrument covers a frequency range of 1 to 400 MHz and has a cali-
brated rf output of from + 10 to
- 60 dBm. Flatness of ±0.25 dB is accomplished with p-i-n diode leveli ng and both harmonic and nonharmonic spurious signals are 30-dB below the output. Sweep linearity is 2%.
CIRCLE NO. 343

Digital temp meter comes in DIN case
Columbia Research Labs, Woodlyn. PA 19094. (215 ) 532-9464. $350; 6 wks.
Model DT-103 digital temperature meter is packaged in a DINstandard case measuring 3.780 x 1.890 x 3.750 in. The instrument displays directly in degrees C or F on a 0.55-in. 3-1 / 2-digit display . A single platinum resistance probe covers - 200 to 500 C. Accuracies range from ± 3 C over the full range to ± 1 C from - 100 to 100 C.
CIRCLE NO. 344
Sig gen tunes from 1.5 to 80 MHz in one band
.. .. (
r--· ---··-..,.-- I!;-~-ili.... -:~:-_- -.:,,.;
Logimetrics, 121 -03 Dupont St. , Plainview, NY 11803. (516 ) 6814700. $2275; 60 days.
Model 950A FM-AM signal generator is continuously tunable over the range of 1.5 MHz to 80 MHz. The unit offers direct 5-digit frequency readout and is said to be the lowest priced generator in its class to provide this feature. Calibrated FM deviation of 0 to 10. and 30 kHz is read directly from a meter on the front panel. FM
distortion is less than 3%.
CIRCLE NO . 345
PROM copier features hexadecimal key entry
Technitrol, Inc ., 1952 E. Allegheny Ave., Philadelphia, PA 19134- (215 ) 426-9105. $850.
Model 107K is a new PROM programmer/ copier/ reader/ v er i fier with hexadecimal keyboard for entry of data and addresses. The unit provides auto-copy between selectable minimum and maximum addresses, programs or lists addresses sequentially or · random ly, verifies master to copy while reading or writing, stops on error detect, displays copy data and address in "read," and displays keyboard data and address in "write."
CIRC LE NO. 346
ELECTRONIC DESIGN 7, March 29, 1976

Make lhe SWilch...

Fujitsu quality miniature power relays

1111111111111111111111111111111111111 Are you a maker of vending machines, control FU.JITSU equipment, business machines, communications gear, 1111111111111111111111111111111111111 or entertainment products? If so, then
chances are you're a large consumer of miniature power relays, especially in the up-to-10-amp range. If you think about it for a minute, you're probably willing to consider an alternate source for your relays, if this maker can match the quality and performance of your present source's
products, yet at a price that will spell savings for you . Wei I, now that you've thought about it, take a look at what Fujitsu has to offer. Fujitsu is now marketing its FRL250-series of top quality miniature power relays. Proven and high performance, the FR L250-series is

available in basic open or enclosed models, delay models, or latching models, and all with the same wide selection of mounting hardware and convenience accessories for topnotch operation to meet your every need. You can choose either DC operation with coils rated at from 6V to 11 OV or AC operation of from 12V to 240V. Contact arrangements available are from 1 Form C to 3 Form C to provide the widest selection. And, of course, all relays are in full
compliance with applicable electrical safety/ performance standards. Fujitsu FR L250-series miniature power relays. They're a proven alternative, fully pin compatible with leading models, and at prices that will make you wonder why you didn't think Fujitsu before.

FUJITSU LIMITED

Comnumicationj and lLectronicj
Marunouchi, Tokyo, Japan
For further 1nformat1on please contact ·Components Oivision(Head Office): Syuwa Onanmon Bldg . 1-1 . Shinbash1 6·chome. Minato-ku. Tokyo 105. Japan Phone Tokyo(03) 437-2111 Cable FUJITSULIMITED TOKYO Telex 2422808 FT SIN J · New York Office:680 Filth Avenue. New York.NY 10019. U S A Phone 12 12) 265·5360 Telex 23 234969 · Fujitsu California, Inc.: 1135 East Janis Street . Carson . Californ ia
90746. us A Phone (2 13) 636-0858 . 537-8930 Telex 230 673387 · London Office: Norman House 105/109 Strand. London.WC 2. England Phone 240-0461 /0462 Telex 51 22305

MAIN PRODUCTS OTelephone Exchange Equipment DCarrier Transmission Equipment DRadio Communication Equipment OSpace Electronics Systems DElectronic
Computers & Peripheral Equipment o Telegraph & D~ta Communication Equipme nt DRemote Control & Telemetering Equipment D Elec tronic Components

CIRCLE NUMBER 76

ELECTRONIC DESIGN 7, March 29, 1976

121

Step-by-step coverage of defense radar system design ...

llTRODUCTIOI TO DEFEISE RADAR SYSTEMS EIGllEERllG
James N. Constant
This all-inclusive handbook covers virtually every facet of radar technology that must be mastered in order to design a complete defense radar system. In fact , it concludes with a step-by-step procedure for specifying and designing a complete radar system for a given application. Separate chapters cover target characteristics; radar detection; radar receivers; radar system error model; flight of a ballistic missile; ballistic reentry trajectories; trajectory prediction; radar data processing; reflector antennas; and array antennas. Order your 15-day examination copy today! #9194, 344 pages, cloth, illustrated, $22.95

Power-supply performance
How to make accurate load regulation measurements by using Kelvi n four-terminal connections is covered in a bulletin. Proper metering techniques and line sources as well as t hermal environment and difficulties in measuring tempco are discussed. Deltron, North Wales, PA
CIRCLE NO . 347
Audio products
How to use low-frequency wave and spectrum analyzers to measure distortion, frequency response, wow and flutter, signal-to-noise ratio and cross-talk of hi gh-quality au dio products are detai led in a 16-page brochure. Hewlett-Packard, Palo Alto, CA
CIRCLE NO. 348

15-DAY FREE EXAMINATION!
f Y l Hoyden Book Company, Inc .
~ 50 Essex Street Rochelle Pork, N.J . 07662
0 Please send me my copy of INTRODUCTION TO DEFENSE RADAR SYSTEMS ENGINEERING to read and use for 15 days. At the end of that time, I'll send a check or money order for $22.95, plus postage and handling, or return the book and owe absolutely nothing .
0 I wont to save money! I hove enclosed full amount. Publisher pays postage and handling . I get a complete 15-doy money-bock guarantee.
Nome ------------~ Firm - - - - -- - - - - - - - Address - - - - - - - - - - - - City/ State/ Zip - - - - - - - - - -
76-15

Data-acquisition system
An interfacing scheme used to connect minicomputers to groups of analog transducers and voltage se nsors is described in a six-page note . Circuit drawings as well as a fu ll timing diagram for random and sequential channel operation are included. Datel Systems, Canton, MA
CIRCLE NO . 349
Arithmetic subroutine
A comprehensive, powerful new subroutine used to dynamically evaluate arithmetic expressions is described in a 52-page booklet. This subroutine, written using a modern structured programming compi ler, is available to the higher order language IBM 370 programmer, enabling him to instantly enhance his system by addin g sophisticated a.rithmetic specification to his user communications. National Institute of Health, Div. of Computer Research and Technology, Bethesda, MD
CIRCLE NO. 350

122

Annual and interim reports can provide much more than financial-posi tion information. They often include the first public disclosure of new products, new techniques and new directions of our vendors and customers. Further, they often contain superb analyses of segments of industry that a company serves.
Selected companies with recent reports are listed here with their main electronic products or services. For a copy, circle the indicated number.
Spectra-Strip. Interconnection devices and systems.
CIRCLE NO . 351
Aeronautical Radio (ARINC). A ir-gro u n d-ai r communications service, electronic switching systems and intercity communications.
CIRCLE NO. 352
Franklin Electric. Motors and package-weighing products.
CIRCLE NO . 353
S.R.C. Laboratories. Photomultiplier tubes and fluid-flow indu cing devices.
CIRCLE NO . 354
Bliss & Laughlin Industries. Tools and tool kits.
CIRCLE NO. 355
Nashua. Image forming, adhesive and magnetic recording materials.
CIRCLE NO. 356
SRI. Basic and applied research.
CIRCLE NO . 357
Triangle Industries. E 1e ctri cal products for construction industry, pre-insulated pipe, automatic merchandising machines and music systems, coin-operated phonographs and dollar-bill changers.
CIRCLE NO. 358
Turbodyne. Steam and gas turbine systems and electrical equipment.
CIRCLE NO. 359
Union Carbide. Chemicals and plastics; gases, metals and carbons, and consumer and related products.
CIRCLE NO. 360
ELECTRONIC DESIGN 7. March 29. 1976

Electronic Design

Advertising Sales Staff Tom W. Carr, Sales Director Jean Sunfield, Sales Coordinator
Rochelle Park, NJ 07662 Robert W. Gascoigne Daniel J. Rowland Thomas P. Barth George Mortimer Stan Tessler 50 Essex St. (201) 843-0550 TWX: 710-990-5071
Philadelphia Thomas P. Barth (201) 843-0550
Boston 02178 Gene Pritchard P.O. Box 379 Belmont, MA 02178 (617) 489 -2340
Chicago 60611 Thomas P. Kavooras Berry Connor, Jr. Harry Marshall 200 East Ontario (312) 337-0588
Cleveland Thomas P. Kavooras (312) 337-0588
Los Angeles 90045 Stanley I. Ehrenclou Burt Underwood Neil Canavin 8939 Sepulveda Blvd. (213) 641-6544
Texas Burt Underwood (213) 641-6544
San Francisco 94040 Robert A. Lukas 3579 Cambridge Lane Mountain View, CA 94040 (415) 965-2636
London, Amsterdam, Tokyo, Seoul Malcolm M. Thiele Wood Cottage, Shurlock Row Reading RG 10-QE, England Phone: Shurlock Row 302 & 619 S.T.D. 073 581
Sanders, B. V. Raadhuisstraat 24 Graft-De Ryp, Holland Phone: 02997 -1303 Telegrams: Euradteam-Amsterdam
Haruki Hirayama Electronic Media Service 5th Floor, Lila Bldg., 4-9-8 Roppongi Minato-ku, Tokyo, Japan Phone: 402-4556 Cable: Electronicmedia , Tokyo
Mr. 0 -kyu Park, President Dongbo Intl Corp.World Marketing C.P.O. Box 4010 Seoul , Korea Tel. 76-3910 / 3911 Cable : DONGBO SEOUL Tel ex: EBKOREA K272 86

{ .. ABP

J;;;;r;.'1

ELECTRON IC DlS IGN 7. !Vl a rc h 29 . 1976

OSCILLOSCOPES
with MORE VALUE for your dollar

Today's design engineer needs

more than just a "visual voltmeter" on his bench. So Heath

.~ . . . .

developed a line of scopes that

offers more performance per

dollar than the industry has seen in years. There's sure to be a Heath scope for your application ... at a price that

New Heath/Schlumberger S0-4550 Dual-Trace Scope
· 10-MHz scope with brighter trace & faster writing speed
· Full mu-metal shield to

satisfies the most valueconscious engineer. Compare Heath specs and price before

eliminate display error from electromagnetic interference
· Fully-regulated high voltage power supply

you buy ... learn about quality Write for your free copy of our latest

that counts.

'

FREE ~~~~:::!~~. Catalog.

Heath/Schlumberger.·. pioneers in value-proven instrumentation

CIRCLE NUMBER 81

Quan-Tech Introduces a high-frequency wave and
spectrum analyzer with a range of 1 KHz to 1.5 MHz.
The Model 2525 is a new, high performance Wave and Spectrum Analyzer with many features including electronic sweep. This portable unit offers unequaled capabilities for accurate harmonic measurements
fourier amplitude analysis of complex signals and
Hr-+-+-+-+-+---+-+-1--+-+-+-~spectral density analysis tii====-__;
of random signals.

51

Q uan'-Je~h ®

D111isw1t of SCIEN TIFI C·A. TL AN TA. , INC.

RANDOLPH PARK WEST, ROUTE 10, RANDOLPH TOWNSHIP, NEW JERSEY 07801 PHONE (201) 361-3100 TWX 710 -987 -7946
CIRCLE NUMBER 82 123

Ne~
Literature

-----.... ...._, .

"''

llllll:IS...

Thumbwheel Switches
fOR llGITAl ClllTRll APPUCATID S=
· INS'Tflll\IL°"U'Tl(>H tl!;TlOIJ·-(_"ilT · OOW'UTERS 6 PEA·l'ttEAAL.5 · ...ac;:E$Sc;m. T1'0l..WOVIPMV'f"' · MJMEAJCl>U.Y~ f lW)Ll.EOMACHINfT00<5 · ~UEA l"fllOOUCTSf<··Fll.tEl..ECOMtofl/..!CAT~S

Thumbwheel switches
Photographs, descriptions, specifications, truth tables and mounting instructions of thumbwheel switches are offered in an eightpage catalog. C&K Components, Watertown, MA
CIRCLE NO. 361
IC sample/hold device
Technical specifications for the Model SHM-IC-1, an integrated circuit sample-and-hold device, are given in a four-page brochure. A general description, block diagram and mechanical specifications are included. Date! Systems, Canton, MA
CIRCLE NO. 362
Power supplies
How you can have your own individual power supply by selecting submodular units is illustrated in a brochure. Output voltages, typical output currents and prices are itemized for each model. Power/ Mate, Hackensack, NJ
CIRCLE NO. 363
Measurement systems
A 112-page book contains all published data sheets on the HP 9600 measurement and control systems, networks, software and peripherals. Hewlett-Packard, Palo Alto, CA
CIRCLE NO. 364
124

Rf transistors
A 16-page rf communications transistor catalog contains product information for both 12 and 28 V devices, at specific frequencies, by application from 2 MHz to 1 GHz. Also included is a competitive package cross-reference and an rf transistor cross-reference. Solid State Scientific, Montgomeryville, PA
CIRCLE NO . 365
Proximity switches
Self-contained industrial proximity switches are highlighted in a 16-page brochure. It contains application drawings, product listings, simplified ordering guides, electrical and operating characteristics, drift and sensitivity charts. circuit diagrams, schematics and mounting dimensions. Micro Switch, Freeport, IL
CIRCLE NO . 366
Digital data processor
The CP70A second generation digital data processor is pictured, described and specified in an eightpage brochure. In-depth di scussion is devoted to the nature of and uses for the many standard programs available. California Instruments. San Diego, CA
CIRCLE NO. 367
Discrete semiconductors
A 112-page discrete semiconductor guide contains technical specifications and application data on field-effect transistors, dual fieldeffect transistors and dual bipolar transistors. The guide groups products by application with a comparison table of key parameters for each device. Intersil, Cupertino, CA
CIRCLE NO. 368
Analog IC designs
··101 Analog IC Designs," a 150page book, contains practical designs for amplifiers, comparators, current sources, flip-flops, gain control circuits, gates, op amps, oscillators, phase detectors, PLLs, Schmitt-triggers, timers and voltage regulators. The book costs $3 prepaid. Interdesign, 1255 Reamwood Ave., Sunnyvale, CA 94086
INQUIRE DIRECT

Electronic Design
ELECTRONIC DESIGN'S function is:
· To aid progress in the electronics manufacturing industry by promoting good design.
· To give the electronic design engineer concepts and ideas that make his job easier and more productive. · To provide a central source of timely electronics information. · To promote communication among members of the electronics engineering community.
Want a subscription'? ELECTRONIC DESIGN is sent free to qualified engineer· and engineering managers doing design work, supervising design or setting standards in the United States and Western Europe. For a free subscription, use the application form bound in the magazine. If none is included, write to us direct for an application form.
If you do not qualify, you may take out a paid subscription for $30 a year in the U.S.A., $40 a year elsewhere. Single copies are $1.50 each.
If you chanlile your address. se nd us an old mailing label and your new address; there is generally a postcard for this bound in the magazine. You will have to requalify to continue receiving ELECTRONIC DESIGN free.
The accuracy policy of ELECTRONIC DESIGN is: · To make diligent efforts to ensure the accuracy of editorial matter. · To publish prompt corrections whenever inaccuracies are brought to our attention. Corrections appear in " Across the Desk." · To encourage our readers as r esponsible members of our business community to report to us misleading or fraudulent advertising. · To refuse any adverti sement deemed to be misleading or fraudulent.
Microfilm copies are available of complete volumes of ELECTRONIC DESIGN at $19 per volume, beginning with Volume 1, 1952 through Volume 20. Reprints of individual articles may be obtained for $3.00 each, prepaid ($.50 for each additional copy of the same articl e ) no matter how long th e article. For further details and to place orders, contact the Customer Services Department, University Microfilms, 300 North Zeeb Road, Ann Arbor, Michigan 48106 telephone (313) 761-4700.
Want to contact us? If you have any comments or wish to submit a manuscript or article outline, address your correspondence to:
Editor ELECTRONI C DESIGN
50 Essex Street Rochelle Park, N.J. 07662

ELECTRONIC DESIGN 7, March 29, 1976

NOW! PM and SHUNT-WOUND

adjustable speed drive systems Cllil:ll PERMAHlHTMAGN£J

I

= - AO.AJSTABlI SPCEDJTOllQUl OflM SYStfMS

AG.llSTo\lltSft'lDIT OllOU£0AM SYSl lMS

CDC-PM describes PM systems, 1/12-1 /4 Hp. 12 pages, 32 drawings, photos
and tables .

CDC-SH describes shunt-wound systems, 1/50-1 /4 Hp. 16 pages. 51 photos, drawings and tables.

. . . from Bodine and Bodine Distributors

Designed and built by Bodine to give 1:1.#.llHI

you perfectly matched speed/torque

control characteristics-provide reli- IU:lilmi
ability and performance you might ex- IB·J&@#I

pect only from far more costly and gi~ ~~ ~~i;,0~~

complex systems.

SPEED CO NT~O LS

Send for catalogs today.

Bod i ne Electric Company, 2528 W. Bradley Place, Chicago, IL 60618 CIRCLE NUMBER 77

We offer the fo llow ing for O EM's producing their ow n keyboa rd s.

- Keyswitches in 3 sizes for 1/2", 5/8" or 3/4" centers

Go ld Bar mechanica l contacts or sealed contacts

Front panel relampab le lighted mode ls

Single and doub le po le co ntacts in-

clud ing NC

Alternate action models Doubleshot mo lded keytops for 3/4"

'"""""'

or 5/8" mounting

Easy change legend systems

100,000 pc. quantity prices as low as $0.19 each

"'"""'""

Letterhead req uest or phone call brings

free sample switch w/keytop ...

u

MECHANICAL ENTERPRIS ES, INC.

8000 Forbes Place Spri ngfield , Virgi nia 2215 1

(703) 321 -8282

TWX 710-832-0942

In Germany . NEUMULLER GMBH, MUNICH In U. K. . TEKOATA Ltd ., STOKE -ON-TRENT

CIRCLE NUMBER 78
ELECTRONIC DESIGN 7, March 29, 1976

i****B**i*c*e**n**t*e*n**n**ia**l**i**

i Issue -.Desl!lll · i

i** JU~

i * *

*t SUPPLY

* t

t LIMITED

t

t* *t We've saved a limited number of * * copies of t he unique 254-page February * * 16th Bicentennial issue of Electronic * * Design. It traces the historic and tech -
t t no logical developments of the electronics
* * industry from the Colonial period to * * today. * * In a message from the White House
t t published in the Bicentennial issue,
* * President Ford commends the issue as
* * "a special part" of our nations's 200th
* * anniversary. t t If you'd like an extra copy as a * * momento of this historic event, we' ll * * be happy to provide it at $4. t t Hurry! When the supply runs out * * you'll have to wait another hundred * * years for anything like it!

*t* ---------------**t Bicentennial Issue

* * * Electronic Design Hayden Publ ishing Company, Inc.

*

* * 50 Essex St., Rochelle Park , N.J . 07662

*t !* Please send me __ copy (copies) of Electronic
* * Design's February 16 Bicentennial issue at * * $4 each. I enclose my check for

* Name * Title

* *

****:****ACod*mdrpe*assn*y *******************:

125

quick ad1

New and current products for the electronic designer presented by their manufacturers.

R21

Thin-Trim variable capacitors provide a reliable means of adjusting capacitance without abrasive trimming or interchange of fixed capacitors, Series 9401 has high Q's and a range of capacitance values from 0 .2-0.6 pf to 3.0-12.0 pf and 250 WVDC working voltage. Johanson Manufacturing Corporation, Boonton, New Jersey (201) 334-2676.

THIN-TRIM CAPACITORS

181

SYNCHRO TO BCD CONVERTERS: 3 or 4 decade, unipolar or bipolar output, adjust·
able scale factor, ±6 or ±30 minute accuracy, 60 or 400 Hz input, zero offset adjustment, module 2.6 x 3.1 x .82" H. Unit Price from $395 ea. other CCC products are Synchro to Digital or DC, Digital or DC to Synchro Converters, Solid State C. T.'s or CDX's, and Absolute Encoders. Send for Free Catalog & Application Notes. Computer Conversions Corp., East Northport, N.Y. 11731(516)261 -3300.

SYNCH RO TO DIGITAL

184

Hi-Rel 12 Bit Ladder Network: Added to the
industry 's most complete standard ladder network product line is the AD850/ U/ F/ 883. The ladder is a 12 bit binary current network for user configured avionics systems where m inimum space, weight and reliability are important. Accuracy is Y, LSB of 12 bits. Price is $50.00 in 100's. Analog Devices, Norwood, Mass. 02062 617 -329-4700.

HI -REL 12 BIT LADDER NETWORK

187

MINIATURE IRONLESS ROTOR DC MOTORS offer efficiencies to 80 %, low in · ertia, rapid response and high starting torque . 24 and 12 VDC models available . Motor time constants are 17 and 23 MS respectively. Rotor torque is 100 and 50 gem and starting torque 600 and 230 gem , respectively . 12 VDC units can be ordered with either a single or extended double shaft. Tach versions also available. For reel and capstan drives, chart and pen drives, etc. North American Philips Controls Corp. , Cheshire, Conn . 06410. (203) 272-0301 .

IRONLESS ROTOR

182

Basic Electricity & Basic Electronics by Van Valkenburgh , Nooger & Neville, Inc . Derived from the COMMON -CORE Train· ing Program initially developed for the U.S. Navy. Thorough, comprehensive cov· erage. Available in separate paperbacks or cloth volume. Write for FREE brochure . Hayden Book Co., Inc., 50 Essex St. , Rochelle Pk, N.J. 07662 (201) 843-0550.

TRAINING TEXT

185

New Electronic Gage, Easy To Use. Thickness, Alignment . . . .diameter or deviation measurements, concentricity, orbit tracing, etc. Accuracy up to ± microinches (± 0.001 inch), resolution <.. 10 microinches . Utilizes non -contacting inductive measuring techniques-unaffected by oil , grease, or water. Replaces LVDT, air gage, dial indicator, micrometer, $1,995. Ask for information on KD-2602 · 2S. Kaman Sciences Corporation, P.O. Box 7463, Colorado Springs, Colorado 80933. (303) 599-1500

ELECTRONIC GAGE

188

'llilll!!~ll'I l<Z .<?J
~

The AMP Box Connector is ideal for sys· terns with up to several hundred con tacts. It features an innovative "box" contact design that accepts square, rectangular, round, or formed channel pins. Available in many pin and receptacie con figurations and with external keying. From the people who offer technical assistance at its best: AMP Incorporated, Harrisburg, PA (717) 564-0100 .

AMP BOX CONNECTOR

183

THERMOELECTRIC MODULE, a remark· able value for only $20 (ppd.), can be used
in water coolers, small refrigerators, hot
and cold temperature sources, spot cooling for electronic components and other applications. Operates at 3 .5 VDC, 8.5 amps, ~T Max at Qc Zero is 60°C, Th is 50° C, Qc Max. at ~T Zero is 19 watts,
Max. Op. temp is 100° C. Price includes Thermoelectric handbook. CAMBION, 445 Concord Avenue, Cambridge, MA 02138.

THERMOELECTRIC MODULE

186

Model 9201 Power Switch, miniature DPDT toggle is designed to meet international dimensional/electrical specs. Electric life: 25,000 make-and-break cycles
at full load. Contact rating: 6 amps with
resistive load @ 120 VAC or 28 voe . Free
Engineering Sample on request. C&K Com-
ponents, Inc., 103 Morse St., Watertown, MA 02172, (617) 962-0800.

POWER SWITCH

189

" Software Library, developed and maintained by users to provide access to the programming efforts of other handheld, programmable calculator users. Viola 3range invites your programs. Contributors receive free the volume in which they are published . Vol 1 is a source containing practical formulae, skillful prosramming, and imaginative treks into mathematics and engineering. Published ::iuarterly. $6. The Viola Grange, Rt. 2, Box 965, Estacada, OR 97023

APPLICATIONS PROGRAMS

190

EC"s new ECL compatible Logic Delay Module features ECL input and outputs; 16-pin DIP package (.250 high); precise delays from 25ns to 250ns; and with 20% taps-each isolated with 70 ECL de. fan-out capacity. Engineered Components Company, P.O. Box Y, San Luis Obispo, CA 93406 (805) 544-3800.

ECL LOGIC DELAY MODULE

193

-I

New Multi-Slide, Multi Circuit DIP Switches . . . wide variety of switching combinations . Freq. Range Sel. test pt. monitoring, select on test, atten. level selection , program addressing, cross pt. switching, 2 poles, 4 posit., 4 poles, 2 posit. ; 1 pole, 8 posit.; 4 poles 2 posit. (var.) True "break-before-make"; spring-loaded dou-
1ble bearing detent; gold/nickel contact plating; self-cleaning wiping action for consistent performance. Minelco Div., Gen. Time, 135 S. Main St., Thomaston , CT 06787 (203) 283-8261

DIP SWITCHES

196

The Model 1000 Directional Wattmeter is an accurate and portable insertion RF wattmeter using plug-in detectors and quick-change RF connectors, which measure forward & reflected CW power. The Model 1000 features a large scale, easily read meter movement. Standard ranges are 5 watts to 10,000 watts; frequency range is 2 to 1,000 MHz. TUCKER ELECTRONICS CO., PO BOX 1050, GARLAND, TEXAS 75040 (800) 527-4642 (In Texas Call (214) 348-8800)

RF WATIMETER

191

Resident COBOL compiler system for the

8080 microprocessor. Runs on any 16.K

RAM system. With a few exceptions, the

level of COBOL offered (relative to ANSI

X3 .23-1974) is: nucleus level 2, table

handling level 2, sequential, relative and

indexed 1-0 level 1, and sort-merge level

1. Reference manaal $6. Also available:

complete disk operating system including

a powerful job control language, an as-

sembler, a text editor, a debugging sys-

tem, file utility routines. Mini-Software

Inc., Box 7438, Alexandria, VA 22307 .

COBOL COMPILER

194

Application Information
· Power Supplys · DC/ DC Converters ·Microprocessor Supplys · Pricing · Specifications · Discounts
SEM ICONDUCTOR CIRCUITS, INC.
306 RIVER STREET · HAVERHILL. MASSACHUSETTS 01830 TEt 1617 1373-9 104

CONVERTER CATALOG

197

Introduction To Defense Radar Systems Engineering. Excellent introduction and practical reference to radar systems design and applications. # 9194, 260 pp., $22.95. Circle the Info Retrieval No. to order 15-day exam copy. When billed, remit or return book with no obligation. Hayden Book Co., 50 Essex St., Rochelle Park, N.J . 07662

RADAR SYSTEMS

192

A FORMS FEED TRACTOR slewing at 37 lps with 140 in/oz of torque. Electronic vernier adj. sets TOP OF FORM: quarter, single & double line feed in forward or reverse are standard. Options of PERF. SKIP, PAPER FEED TIME OUT, END OF FORM SENSING & SELECTABLE TOP OF FORM\ are available. The design assures operating simplicity, long life and trouble free performance in heavy duty operation. TRAKTEX 45 Ryegate Terr. Monroe, Ct. 06468 203-261 -9011

FORMS FEED TRACTOR

195

STRIP/BUS BY ROGERS. Low Cost Bus· sing Systems; easy installation, reliable solder joints; greater pin exposure. Write or call for details. Rogers Corporation, Rogers, CT 06263 . Phone (203) 7749605.

STRIP/BUS

198

Advertiser's Index

Advertiser

Page

AMP, Incorporated _______ _____ __ _____ ___ ____ J26

A VX Ceramics ------ ----------- -- ----- --------- - 24 Abbott Transistor Laboratories, Inc. 6 Advanced Micro Devices_____ ___ __ _____.54, 55
Ailtech, A Cutler-Hammer
Company -------------------------------------- 113 Allen Bradley Co·----------------------- ------- 1 Ampex Memory Products Division.... 77 Amplifier Research Corporation........ 106 Analog Devices, Inc. __________ _________ ______ _126

Arnold Magnetics Corp.....................118

BBeolddienne CEloercptorircatiCoonmp--a--n--y-----_-_-_-_-_-_-_-_·_-_-_-_-_-_-_-_41,255 Bourns, Inc., Trimpot
Products Division ____ ______________Cover II Buckbee Mears Company ................ 65

C & K Components, lnc..................... 126
CTS Corporation ·······--·-········--Cover III Cambion .. ........................................ .... 126 Cambridge Thermionic Corporation.. 113
Centre Engineering -------- ·-····-··--·-··--··· 115 Centralab, The Electronics
Division of Globe-Union, lnc....... 117 Circuit Technology, Inc.....................109 Computer Conversions Corp.............126 Computer Products, Inc..................... 109 Continental Connector Corporation.. 72 Continental Specialties Corporation.. 38
Curtis Adams ----·---·····--········-··--···-----127
Data General Corporation .............. 51 Data Precision Corporation................ 91

Advertiser

Page

Data Translation, lnc.........................115

Dialight, A North American Philips Company ............................ 45

EECO .................................................. 23 Electronic Design ..... .. ..... 116, 125, 129
Electronic Molding Corporation........ 64 Elexon Power Systems ...................... 41 Engineered Components Company.... 127

Fairchild Micro Systems Division of Fairchild Camera and Instrument Corporation.......... 79
Fujitsu Limited ·······-···-----------···-········ 121

Gold Book, The ......................110, 111 Gould Inc., Instrument Systems
Division ···-··--····--·--························ 113

Hayden Book Company, Inc................................. 122, 126, 127
Heath Company ------ --· -·····--···---··-····-·--123 Heinemann Electric Company............ 37
Hewlett-Packard -·--··········----------9 thru 18 Hughes Aircraft Company,
Microelectronic Products Division 35

ITT Cannon, A Division of International Telephone and
Telegraph Corporation -------------·-··· 97 Intech, Incorporated ········-···········--···· 108 Intelligent Systems Corp..................... 106
International Rectifier ........................ 78

Johanson Manufacturing Corp. __________ J26

classified ad

LINEAR CIRCUIT DESIGN
ENGINEER

Want t~e whole challenge from design to end use?

COME TO EAi...

It's the world's leading producer of analog/hybrid computer systems that's providing this comprehensive opportunity-requiring a BSEE with experience in linear and dlgltal circuit design, with emphasis in the linear area.
Your assignments will cover design, development and testing of pre· cision operational amplifier circuitry as utilized in analog/hybrid computers--inclusive of integrators, multipliers, analog switching matrices, multi -variable function generators, A

to D and D to A converters, sample hold amplifiers and power supplies. in addition, you'll be involved with the end use of circuitry, employing the system of which it is a part.
Position offers fully paid relocation to our corporate headquarters in desirable Jersey Shore area, an excellent starting salary plus full package of company benefits. Write and / or send resume, in confidence , with sal ary history, to: B. Evenson, Corporate Staffing.

ELECTRONIC ASSOCIATES, INC.
Dept. ED329, West Long Branch, New Jersey 07764 An Affirmative Action Equal Opportunity Employer-Female/Male

128

Advertiser

Page

Johnson Company, E. F ............... ... ... 39

Kaman Sciences Corp............. ... ......... 126 Kepco, Inc. ·······--·················-------------- 42

Litronix, Inc. -----······ ······------- ---------- ---- 103

MCG Electronics ··-··-------·-····--·-···-···--- 130 Mechanical Enterprises, lnc............... 125
*Memb ra in Ltd . -----·-··-----------···-----···· 2 Mepco/ Electra, lnc. --····--- ----------------· 40 Mesucora 76 ···----------··· ··---·-··· ·---- ---- --- 119 Micro Devices Corp .. ................. ..... ... 107 Micro Electronic Systems, lnc........... 117 Minelco Di vision/ General
Time Corp. ----------····---------·---·······--127 Mini-Software, Inc. -- ----- ----------- ------ -- --127 Monsanto, United Systems
Corporation Subsidiary ·· -------- ------ 86 Mos Technology, Inc......................... 67 Motorola Semiconductor
Products, Inc. ·····-····--------- ------------- 25
National Semiconductor Corporation 31 North American Philips
Controls Corp. ........................ 107, 126

Optron, Inc. ··············· ···--·····-· -·······-···· 7
*Philips Industries, Electronic Components and Materials
Division ·······--············--·-----······· -·-· l l4A *Philips Instrumentation
Recording ............................... . l 14B-C Pioneer Magnetics, Inc. .................... 73 Potter & Brumfield, Division of
AMF, Incorporated ...................... 29 Power/ Mate Corp. ............................ 116
Power Tech, Inc. ···········--·-········------ --100 Precision Monolithics, Incorporated 33
Pro-Log Corporation ····-----··········----- 19
Quan-Tech, Division of Scientific Atlanta, lnc..................... 123

RCA Solid State........................Cover IV
Ramtek Corp. ·····----················----------- 90 Raytheon Company,
Ocean Systems Center ···-·-····· ····--- 104 Rental Electronics, Inc........... ............ 20
*Rifa of Sweden -·-······· ·----···· ·····---- 114D Rogers Corporation ----··············-- ----- --- 127
Semiconductor Circuits, lnc............. 127 Simpson Electric Company................ 27 *Sodeco SAIA Ltd........ ... .................. 20 Sola Electric, Division of
Sola Basic lndustries...................... 114 Spectrol Electronics Corporation .... 66 Sprague Electric Company................ 53 Stahlin Co., lnc.................... .... ......... ..117

TRW Power Semiconductors, an Electronic Components Division of TRW, Inc............. .................. .... 87
Technical Communications, Inc. ______ 48 Technical Materials, lnc... ..... ... ... .... ... 105
Teledyne Crystalonics --------······--········ 99 Teledyne Relays, A Teledyne
Company ---- ---------------·----········-···--·- 2 Teledyne Semiconductor ·········----- ------ 56 Tenney Engineering, Inc..................... l 07 Texas Instruments, Incorporated....46, 47
Traktex ·-·--····--------- --- ------ --- -··········-······ 127 Triplett Corpo11ation ................. ......... 93 Tucker Electronics Co. __ ______.............. 127

United Systems Corporation, A Subsidiary of Monsanto............ 86

Victoreen Instrument Division, Sheller-Globe Corporation .......... 95

Weston Components ..........................119

*Advertisers in non-U.S. edition

ELECTRONIC DESIGN 7, March 29, 1976

Use this form for Change of Address or New Subscription Only.

MAIL TO :

Elac1ronic oasian

MR .O
Ms. o

I
Area Code

I
Office Telephone

1st 2nd

P.O . BOX 13803, PHILADELPHIA, PA. 19101 Initia l

Lasl Na me

Ti tl e

FREE SUBSCRIPTION APPLICATION

Do you wish to receive (continue to receive)
ELECTRONIC DESIGN? QYes QNo

Date: Signature: Does not obl igate me or mv company

wish to receive (do not w ish to receive) other

O 0 solicitations.

Yes

No

ALL SUBSCRIBERS : Please fill out compleU!ly, the name and address ' portion, even if the information on your label is the same. (For prompt, accurate processing remember to affix label in the space pro vided above.) Do not use periods, commas etc.

To qualify please answer all questions carefully.

Independent consultants must attach business

card.

~

, o Title: (Insert letter)

A President B Vice President
c Vice President of Engi neeri ng
D T ec hnical Director E Ch i ef En gi neer F Pri nci p al E ngineer G Research D irector H Sectio n Head

J Project Engtne~r K Senior Engmeer L Group Leader M Dep t. Head N MTS 0 Engineer p Co n su ltant
R Scientist
s Physicist

D 2

Your principal job function : (Insert code)

1 Ge neral and Corporate Management

2 Des ign and Development Engineering (c1rcu1ts, components,

eq u ip ment systems)

3 Eng ineeri ng Services (evaluation. quality control , reltab1l1ty ,

c>:
0

standards, test)
4 Basic Research 5 Manu fact u ri ng and Production 6 Engi neering Assistants (draftsman, lab ass1s1an1, technic,anl

c:

7 Purchasing and Procurement

0

8 Marketing includi ng Sales

·~

9 Other Person nel (explain)

...

u

1i
e:nI

Plant Your own work

3 0

D The primary end product (or service performed) at your plant, and the product

3:

(or service) that is your own work . (Insert

z.C.V.

code in each box even Ff the same)

0

A A La;ge Computers

""C..V''.

B B M1n1-Computers

c

c Compu ter Peripheral Equipment

D D Data Processing Systems !Systems Integration)

'tJ
.~...
0

T

T Office and Business Machines

E E Test, Measu reme n t and In strumentation Equipment

F

F Co mmun icatio ns Systems and Eq u ip ment

H H Naviga t io n and G u ida nce Systems and Eq u ipment

J

J Co nsumer Entertai n ment Electronic Equipment

....uccCecVa::n
..0..

G G Co nsu mer Electro n1c ·Appl1ances

N N Ot her Consu mr Electro n ics

K K In dustrial Co n tro ls, Systems and Equipment

L

L Compo nen ts and Sub Assemblies

M M Ma teria ls a nd Hardware

a

a Aircraft, Missi les. Space and Grou nd Support Equ1pmen

p

p Oceanog raphy and Su pport Equipme n t

E...

R R Medica l El ectro n ics
u u Indust rial Co mpanies wit h in the O EM incorporating

~

Elect ronic Eq u ipme n t 1n their e nd product , not else· where classified

v v Independen t Research , Test and Design Laboratory

and Co nsu ltant. (O nl y tf y ou are not con nected with

a m anu fac tu ri ng company .I
x x Governmen t Agen cy and Miiitary.

2

2 Ind ustr ial Co mpan ies usi ng and /or incorporating any

Elec tron ic produ cts 1n th eir man uf act u ring, research

or development ac tivit ies.

1

1 Co mmerc ial Users of Electro n ic Eq u ipme n t

3

3 Distribu tor

4

4 School, Un iversity or Librar y

5

5 Ot her (ex plai n )

8

Products you specify or authorize purchase of :

(Check all codes that apply.I

0 12 Co mputer Peri p herals

0 1 Resistors and Capacitors

0 13 Computer Components

0 2 Connectors

0 14 Cabinets and Enclosu res

0 3 Switches and Relays 0 4 Fu nction Modules : Op Am ps, Converters, etc . 0 5 Pote n tiomete rs

0 15 Panel Meters, Analog or 01g1tal 0 16 Readout and Display Devices 0 17 Rotat in g Componen ts

0 6 Test a nd Measure men t Equip ment

0 18 Cooling Products

0 7 Computers. Mediu m and Large

0 19 Printed Circuits

0 8 Electronic Power Supplies

0 20 Calculators

0 9 !Cs and Sem iconductors

0 21 Indicators including LEDs

0 10 Microwave Devices

0 22 Materials, Potting and Stripping

0 11 M1n1computers

0 23 Communications Equi pment

D 7

Please write in box total number (other than self) to be

served by this subscription at this address and list in-

dividuals and th eir titles below. If no other person is

served please indicate " O" in the box at left.

Name (Please Prtnt )

T i tl e

9

Do you specify or buy through distributors?

0 YES

ONO

10 Minicomputers at this address :

3 Ci nci n na t i Milacro n
c Co mputer Autom atio n
D Co ntro l Da ta E Data Ge neral F D_ig_i tal Eq u ipme n t I General Au tomation K Hewle tt Packard M Ho neywe ll 0 IBM N Interdata 7 Mic rodata
Modular Computer ROLM v ~stems Eng ineering Labs 9 Texas Inst ruments x Va ri an Other

Model Oty . M o d el

Oty.

g. s· m
"' "' mr(") -t ::J:I 0 z
a. .c ::Ji c::
cQ ' Ql :::i ....
,o am.·
"~' ~"'.
:::i :::i
g_ ~
"' OJ
c":'r a:::i. :a::i. ":::'i
aOJ. ":;'·
"'"' ":-::'i· -:'

... ... "' 3."c:':
~

,
::Ji ~ <

)> -t

;ac::;:..-

:;:;:;i--
.c

'C
6'

::Ji
:::i-

~

c::
~

"' ?

, .c ·
:::i-

Q_
;:;
c::

6"
:::i
,OJ

...... ... "'.... 0

iii'
5·

n 0

"' :::i :::i

~

0

3 < Q

"'0
:::i

!!. "g'

<... ... :::i-
""'' 0

n ~:
:::i

:::i-
c:

"'"' "'n

a:::i.

0
3

Ci !!.
:::i

<"Ci

,'C
OJ

c:: OJ

OJ
... ;;;-

0-
;;;-

::Ji ~
:::i-

... "' ~
:::i-

a.
OJ

CD

0
.c

?'

&

"' ~ c::
~

-t

:::i

:::;; :::i-

<

"'C
c::

.... g' O, ' 'cC:: ~

""'' "' OJ
,

~
;;;·
,:::i- 6 " :::i

4I I

Your design function : (Insert each letter that applies)

A I do elect ron ic d esi gn or devel o pmen t en gi nee ring work B I superv ise electron ic des ign or devel o pme nt engineering work C I se t s tandard s for, or eva lu ate e lectro n ic design compo nents,
systems and ma ter ials

D 5

Your principal responsibility : (Insert code)

1 Managemen t o ther than Eng ineeri ng

3 Eng inee ri ng

2 Engineering Managemen t

D 6

Please estimate: (Insert letter)

The n umer of electron ic e ngineers at this address :
IAI 1 IBl 2-5 ICl 6 -19 IOI 20-49 IEl 50-99
IFI 100-249 IGl 250-499 I HI 500-999 IJl Over 1000

For change of address only attach old mailing label here.

Product Index

CROWBAR
Here's positive low cost protection for your IC's, transistors, power supplies and pc cards.
The LVC-1 A crowbar switches to a short circuit whenever the voltage across it exceeds a specified level.
Any trip voltage level between 4 .7V
and 200V :t. 10% can be selected. The
unit will handle a peak current of 50 Amps (Bms) end 3A continuously . MIL Temperature range. Call Mike Coyle for applications assistance.
Full line of protection modules for every hi-lo voltage/ current requirement. Write or call for Catalog 749 .
279 Skidmore Road Deer Park, New York 11729 Telephone: 516 - 586-5125
CIRCLE NUMBER 85
Please Help
Children Live
Research is our only weapon against childhood cancer. St. Jude Children's Research Hospital, which is non-sectarian, is the largest childhood cancer research center in the worl3. Please join in the fight against childhood cancer. Send your special gift now.
--
~ST.JUDE
CHILDREN'S
RESEARCH
HOSPITAL
Danny Thoma s, Founder
Send contributions to: MEMPHIS, TENN. 38101 This space donated by publication
130

Information Retrieval Service. New Products, Evaluation Samples (ES), Design Aids (DA), Application Notes (AN), and New Literature (NL) in this issue are listed here with page and .Information Retrieval numbers . Reader requests will be promptly processed by computer and mailed to the manufacturer within three days.

Category

Page IRN

Components

capacitors

39

19

capacitors, ceramic

115 66

chips

24

10

keyboards

121

78

motors, de

107 54

potentiometers, trimming II 284

relay, solid-state

37

17

relays

29

13

relays, T0-5

2

3

relays, sensitive

118 336

resistor networks

117

69

resistors

1

2

resistors

41

21

switch, thumbwheel

118 338

switches

45 23

trimmers

119

74

trimmers

Ill 285

Data Processing

CRT terminal

106 52

emulator, in-circuit

90 41

memory, µC

77 36

memory, core

116 335

multiplexer, disc-storage 115 332

PROM eraser

115 333

printer

116 334

Discrete Semiconductors

crowbar, de

130 85

crowbars, de voltage 114 330

diodes, varactor

112 327

isolator, opto

114 331

isolators

7

6

LEDs

112 328

optical coupler

99 46

power Schottkys

87

40

silicon transistors

100 47

transistors, microwave 114 329

transistors, switching 112 302

Instrumentation amplifier, broadband analyzer charge amplifier DPMs oscilloscopes oscillograph PROM programmer pocket DVM pulse generator rental equipment signal generator sweeper temperature meter VO Ms

106 53

123 82

120 340

27 12

123 81

113 62

120 346

120 342

120 341

20

8

120 345

120 343

120 344

93 43

Integrated Circuits
d I a converters
DAC linear ICs RAM, 16-k

25

11

102 309

IV 286

.101 305

Category

Page IRN

RAMs shift registers synthesizer

102 306 102 307
102 308

Microprocessor Design

assembler, cross

50 553

computer, micro

49 552

computer, 8080

compatible

52 556

emulator, µP

50 554

instrument

49 551

m!croprocessor

79 38

m 1croprocessors

19

7

tool, system development 52 555

Modules & Subassemblies

converters, d /a

109 326

custom hybrids

109

58

data-acquisition system 115

65

drive systems

121

77

f Iv/ f converters

108

57

line driver

108 304

microcircuit modules

35

16

subsystems, data-acq. 109 325

Packaging & Materials

clips

38

18

connectors

72 34

connectors, circular

97

45

connectors, heavy duty 106 324

electronic comp. catalog 113

61

flexible circuits

51

26

gold inlay

105 51

gripper

64 30

insertion tool

117 71

sockets, transistor

105 321

solvent, epoxy

105 322

test chamber

107

55

tool, crimp and cut

105 320

wire, cable and cord

5 234

wire stripper

104 3.01

Power Sources power supplies power supplies power supplies power supplies power supplies

6

5

40

20

73

35

109

59

114 64

digital data processor 124 367

discrete semiconductors 124 368

IC sample/hold device 124 362

measurement, control

sys.

124 3·64

off-the-shelf power

supplies

124 363

proximity switches

124 366

rf transistors

124 365

thumbwheel switches 124 361

ELECTRONIC D ESIGN 7, March 29, 1976

Million-dollar performance for only a quarter.

Fantastic! Small size, great perfor-

And the serrated adjustment knob

mance and CTS reliability are only doubles as a dust cover to protect the

three reasons you should use our NEW element from dirt, oil and other con-

series 375 single turn cermet trimmers. taminants.

The ·1ow 25¢ price tag is still another.

- CTS 375's, in six popular terminal

It's a lot for so little. But you expect

styles , feature a low ± 100 ppm/°C that from a company that's put millions

standard temperature coefficient- into electronics for industry. For com-

throughout the resistance range. Power plete information, write CTS OF

rating, 1 watt at 40°C; Y2 watt at 70°C. BERNE, INC., Berne, Indiana 46711

CDRPO,':!~J~'i!.~ e. CRV of 2%. Settability of .03%. CTS

or phone (219) 589-3111.

A world leader in cermet and variable resistor technology

CIRCLE NUMBER 285

What's new in solid state ...
RCA offers11 more
Gold CHIP LICs
at plastic prices.

Now you can replace ceramic with plastic,

and get the reliability of ceramic at plastic prices.

Eleven new Gold CHIP standards give you 11

new ways to get the cost and reliability benefits of

gold plus Qhip !::fermeticity !n Elastic. In all there

are 26 Gold CHIP LICs with the reliability that

comes from true hermeticity, plus the economy

and ruggedness of plastic.The chip's hermetic -

and the metalization and leads are all of non-

corroding gold. There's no aluminum with its

potential problems.

No problems ordering, either. Just call the

Id CHIP specialist at your nearest RCA Solid

'stributor. And give him the type numbers

· s you ne· '

sy way to

stic prices.

Single Operational Amplifieis

CA101AG ;ic CA107G,* CA201 AG ,* CA207G,* CA301AG,* CA307G ;ic CA741CG, CA741G, CA748CG ;ic CA748G *

Dual Operational Amplifiers

CA747CG, CA747G, CA1458G ~' CA1558G *

Quad Operational CA124.G, CA224G, CA324G,

Amplifiers

CA3401 G*

Quad Voltage Comparators

CA139AG, CA139G, CA239AG, CA239G, CA339AG, CA339G

1A N-P-N Transistor CA3724G, CA3725G Arrays , ...