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42SL80 Thin Training Manual 05/04/2010

42SL80

Original February 11, 2010

Updated May 04, 2010

1080P

Direct View LCD

LCD DV 42SL80

2February 2010

OUTLINE

• Two Inverter Boards

• Main Board

•T-CON Board

Circuit Board Operation, Troubleshooting of :

• Switch mode Power Supply

Section 1

Section 2

Contact Information, Preliminary Matters, Specifications,

LCD Overview, General Troubleshooting Steps,

Signal Distribution, Disassembly Instructions and Voltages

• Ft Control Board

P-DIM (Digital Dimming) Routed from the Main

board to the T-CON to the Ballast.

42SL80

LCD DV 42SL80

3February 2010

42SL80 LCD Direct View Display

Section 1

This Section will cover Contact Information and remind the Technician of Important Safety Precautions for

the Customers Safety as well as the Technician and the Equipment.

Basic Troubleshooting Techniques which can save time and money sometimes can be overlooked. These

techniques will also be presented.

This Section will get the Technician familiar with the Disassembly, Identification and Layout of the LCD

Display Panel.

At the end of this Section the Technician should be able to Identify the Circuit Boards and have the ability

and knowledge necessary to safely remove and replace any Circuit Board or Assembly.

Overview of Topics to be Discussed

LCD DV 42SL80

4February 2010

IMPORTANT SAFETY NOTICE

The information in this training manual is intended for use by persons possessing an adequate background in

electrical equipment, electronic devices, and mechanical systems. In any attempt to repair a major Product,

personal injury and property damage can result. The manufacturer or seller maintains no liability for the

interpretation of this information, nor can it assume any liability in conjunction with its use. When servicing this

product, under no circumstances should the original design be modified or altered without permission from LG

Electronics. Unauthorized modifications will not only void the warranty, but may lead to property damage or

user injury. If wires, screws, clips, straps, nuts, or washers used to complete a ground path are removed for

service, they must be returned to their original positions and properly fastened.

CAUTION

To avoid personal injury, disconnect the power before servicing this product. If electrical power is required for

diagnosis or test purposes, disconnect the power immediately after performing the necessary checks. Also be

aware that many household products present a weight hazard. At least two people should be involved in the

installation or servicing of such devices. Failure to consider the weight of an product could result in physical

injury.

Preliminary Matters (The Fine Print)

LCD DV 42SL80

5February 2010

Today’s sophisticated electronics are electrostatic discharge (ESD) sensitive. ESD can weaken or damage

the electronics in a manner that renders them inoperative or reduces the time until their next failure.

Connect an ESD wrist strap to a ground connection point or unpainted metal in the product. Alternatively,

you can touch your finger repeatedly to a ground connection point or unpainted metal in the product. Before

removing a replacement part from its package, touch the anti-static bag to a ground connection point or

unpainted metal in the product. Handle the electronic control assembly by its edges only. When

repackaging a failed electronic control assembly in an anti-static bag, observe these same precautions.

Regulatory Information

This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to

Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful

interference when the equipment is operated in a residential installation. This equipment generates, uses,

and can radiate radio frequency energy, and, if not installed and used in accordance with the instruction

manual, may cause harmful interference to radio communications. However, there is no guarantee that

interference will not occur in a particular installation. If this equipment does cause harmful interference to

radio or television reception, which can be determined by turning the equipment off and on, the user is

encouraged to try to correct the interference by one or more of the following measures: Reorient or relocate

the receiving antenna; Increase the separation between the equipment and the receiver; Connect the

equipment to an outlet on a different circuit than that to which the receiver is connected; or consult the

dealer or an experienced radio/TV technician for help.

ESD Notice

(Electrostatic Static Discharge)

LCD DV 42SL80

7February 2010

Safety and Handling Regulations

1. Approximately 20 minute pre-run time is required before making any picture performance

adjustments from the Menu.

2. Refer to the Voltage/Current silk screening on the Switch Mode Power Supply.

3. C-MOS circuits are sensitive to static electricity.

Use caution when dealing with these IC and circuits.

4. Exercise care when making voltage and waveform checks to prevent costly short circuits

from damaging the unit.

5. Be cautious of lost screws and other metal objects to prevent a possible short in the

circuitry.

1. Check the appearance of the Replacement Panel and Circuit Boards for both physical

damage and part number accuracy.

2. Check the model label. Verify model names and board model matches.

3. Check details of defective condition and history. Example: Oscillator failure dead set, etc…

Checking Points to be Considered

LCD Direct View Overview

LCD DV 42SL80

8February 2010

Basic Troubleshooting Steps

Define, Localize, Isolate and Correct

•Define Look at the symptom carefully and determine what circuits could be causing

the failure. Use your senses Sight, Smell, Touch and Hearing. Look for burned parts and

check for possible overheated components. Capacitors will sometimes leak dielectric material

and give off a distinct odor. Frequency of power supplies will change with the load, or listen for

relay closing etc. Observation of the front Power LED may give some clues.

•Localize After carefully checking the symptom and determining the circuits to be

checked and after giving a thorough examination using your senses the first check should

always be the DC Supply Voltages to those circuits under test. Always confirm the supplies

are not only the proper level but be sure they are noise free. If the supplies are missing check

the resistance for possible short circuits.

•Isolate To further isolate the failure, check for the proper waveforms with the

Oscilloscope to make a final determination of the failure. Look for correct Amplitude Phasing

and Timing of the signals also check for the proper Duty Cycle of the signals. Sometimes

“glitches” or “road bumps” will be an indication of an imminent failure.

•Correct The final step is to correct the problem. Be careful of ESD and make sure to

check the DC Supplies for proper levels. Make all necessary adjustments and lastly always

perform a Safety AC Leakage Test before returning the product back to the Customer.

LCD DV 42SL80

9February 2010

This section of the manual will discuss the specifications of the

42SL80

LCD Direct View Display

42SL80 PRODUCT INFORMATION SECTION

LCD DV 42SL80

10 February 2010

42SL80 Basic Specifications

• TruMotion 240Hz

• Intelligent Sensor Mode

• Full HD 1080p HD Resolution

• 150,000:1 Dynamic Contrast Ratio (Brightness 500 cd/m2)

• 2.2ms Response Time (Gray To Gray)

• 500 cd/m2 Brightness

•Wide Color Gamut

• Super IPS Panel

• Wide Viewing Angle (178º / 178º)

•XD Engine®

• 24p Real Cinema

• ISFccc® Ready

• Picture Wizard

• AV Mode II (Cinema, Sports, Game)

• 60,000 Hour Panel Life (typical)

• NTSC/ATSC Tuners with Clear QAM

• 2 HD Component Video Inputs

• 2 Composite inputs

• 1 Digital Audio Out

• USB 2.0 (JPEG, MP3, MP4, Divx)

• PC Connectivity (D-Sub 15pin)

LCD DV 42SL80

11 February 2010

Basic Specifications (LOGO Familiarization)

Full HD 1080p Resolution

Displays HDTV programs in full 1920 x 1080p

resolution for a more detailed picture.

LCD DV 42SL80

12 February 2010

TOP PORTION BOTTOM PORTION

Remote Control Familiarization

p/n MKJ61841701

LCD DV 42SL80

13 February 2010

Accessing the Service Menu

To access the Service Menu.

1) You must have the Service

Remote. p/n 105-201M

2) Press “In-Start”

3) A Password screen appears.

Note: A Password is required

to enter the Service Menu.

Enter; 0000

LCD DV 42SL80

14 February 2010

Side Input Jacks

Rear and Side Input Jacks

Main Board

Orientation

Rear Input Jacks

Side AV

Side A/V Input

42LS80 Dimensions

7-7/8"

200mm

24.1/2”

622.3

39.3/8"

1000mm

Remove 4 screws to

remove stand for

wall mount

15.¾“

400mm

21.7/8"

500mm

27.1/8"

688.34mm

Center

7-7/8"

200mm

6.11/16"

170mm

10.1/16"

255mm

2-5/8"

66.04mm

Weight without Stand: 41.2 lb

Weight with Stand: 52.2 lb

1.13/16"

4.572mm

11.5/16"

287.02mm

19.11/16"

500.06mm

12.1/4”

31.15mm

42SL80 Product Dimensions

There must be at least 4 inches of Clearance on all sides

Wattage

Average 210W

Stand By 0.36W

Model No.

Serial No.

Label

Model No.

Serial No.

Label

7-7/8"

200mm

LCD DV 42SL80

16 February 2010

This section of the manual will discuss Disassembly, Layout and Circuit

Board Identification, of the 42SL80 LCD Direct View Television.

Upon completion of this section the Technician will have a better

understanding of the disassembly procedures, the layout of the

printed circuit boards and be able to identify each board.

DISASSEMBLY and TROUBLESHOOTING SECTION

The Stand must be

assembled when TV first

received out of the box.

Decorative Cap

(If Installed)

Must be removed

To take back off.

LCD DV 42SL80

17 February 2010

Removing the Back Cover

The Stand does not need to be removed

Remove the 19 screws indicated.

Pay attention to the size and type of screw

as there are many different types.

Putting in the improper screw when

reassembling may Cause damage.

The top two stand screws

Need to be removed, but

Not the bottom two screws.

Warning: The stand base is

“Glass” be careful, it will break.

If the customer has installed the

decorative Plastic Cap, it must be

removed before the back will come off.

LCD DV 42SL80

18 February 2010

Circuit Board Layout

T-CON

MAIN

SMPS

INVERTER A

FRONT CONTROL (IR)

p/n EBR63322103 KEY BOARD

p/n EBR63609903

LVDS

p/n EAT60667401 INVERTER B

SIDE

A/V

Invisible Speakers

EAB60866701

AC Input

p/n EAY58470001

p/n EBR63774601

Invisible Speakers

EAB60866701

Main

Power Switch

Inverters p/n EAY60750201

42LS80 Connector Identification Diagram

T-CON

POWER

SUPPLY

MAIN

BOARD

P204 P205

SK100

P101

CN1

CN2

CN1

CN5 CN4

P800 P801

P400

Speakers (Front Left)

Speakers (Front Right)

AC In

Main Power

Switch

P803

N/C

TFT Panel

INVERTER

P201

Front Keys

CN3

CN2CN3

P1000

P300

CN201

CN203

INVERTER

CN5

P101

P100 J2

P100

P101

A/V IN

Front “Soft Switch” Keys

FRONT IR

SC1

Black

CN205

MC1

Black

LCD DV 42SL80

20 February 2010

Power Supply Board Removal

Disconnect P201, P205,

P204, P101 and AC In

SK100.

Remove the 6 screws

indicated by the arrows.

SK100

P101

To Main Power Switch SK100 AC In

Caution: Be careful when

touching the back side of

the Power Supply as

some capacitors can still

hold a charge.

P201P205P204 P201 to Main

P205 to Inverter B

P204 to Inverter A

LCD DV 42SL80

21 February 2010

Main Board Removal

Disconnect

P100, P300,

P400, P800,

P801

Remove the 4

screws

indicated by

the arrows.

To A/V

Board

P801

P100

P800

P400

P1000

P300

Remove any tape holding

down any cables.

NOTE: Be sure to check on

top and behind the

Micro/Video Processor IC.

Look for Chocolate

(Heat Transfer Material).

Be sure to transfer to new

Board if present.

Flip the locking tabs upward, pull the LVDS ribbon up and out

SMPS

SPKs

LCD DV 42SL80

22 February 2010

Removing the T

Removing the T-

-CON Board (1 of 2)

CON Board (1 of 2)

Press

In Press

Remove the LVDS Connectors CN1 and CN2

Remove the 3 Screws in the T-CON shield.

There is a small

lip at the top of the

shield, pull straight

out slightly to

remove.

Be careful with the tabs.

They are fragile and will break.

Rock the connector side ways while

pulling the cable out.

LCD DV 42SL80

23 February 2010

Removing the T

Removing the T-

-CON Board (2 of 2)

CON Board (2 of 2)

Flip the Locking Mechanism upward on CN4 and CN5 to release the LVDS cables to the Panel.

T-CON SERVICE POSITION

Remember, these two screws have to be replaced in the board

if the TV is to be run with the T-CON shield removed.

Flip

Downward

Flip

Downward

Pull Out

Pull out (CN3)

LCD DV 42SL80

24 February 2010

Inverter A Removal

Remove 4 screws.

Be careful not to drop these screws. p/n EAY60750201

Includes both Inverters

To T-CON

To SMPS

To Inverter B

CN1

CN3

CN2

CN5

Disconnect

CN1, CN2,

CN3 and

CN5

Backlights

LCD DV 42SL80

25 February 2010

Inverter B Removal

Remove 4 screws.

Backlights

To SMPS

To Inverter A

CN205

Disconnect

CN201,

CN203 and

CN205

CN203

CN201

Be careful not to drop these screws. p/n EAY60750201

Includes both Inverters

LCD DV 42SL80

26 February 2010

POWER SUPPLY SECTION

This set utilizes a Switch Mode Power Supply.

Input Voltages: AC

Stand-By Output Voltages:

•+5V (Stand By 5V) to the Main.

Run Output Voltages:

•+5V (Stand By 5V) to the Main

•12V to the Main

(Video Processing, Tuner B+

and T-CON B+)

•24V to the Main

(Audio B+)

•24V to both Inverters

Run Input Commands from Main:

•PWR-ON (Relay On Command)

Brings the SMPS out of Stand-By

•INV-ON (In and Out to the Ballast)

This line also called “I-C”

Turns on the Backlights

p/n EAY58470001

LCD DV 42SL80

27 February 2010

There are three types of Main Power switch used in LG televisions.

Type 1: Shuts off AC to the Power Supply.

Type 2: Opens ground to the front IR board. (Stand-By 5V Remains, the Main board stays alive).

This prevents any activity of the IR or the Key Board. When the Switch is opened, a line called Power Key pulls up high

when ground opens. When the switch is closed, this same line called Power Key feeds back to the Microprocessor and the

Micro. Turns on the Power.

Type 3: Opens ground to the front IR board. (Stand-By 5V turns off, the Main board is dead).

This prevents any activity of the IR or the Key Board. When the Switch is opened, a line called Power Key pulls up high

when ground opens. This line feeds back to the Main board and from there it routes to the Power Supply. The high tells the

Controller chip to turn off STBY-5V. When the switch is closed, this same line called Power Key now goes high and feeds

back to the Power Supply and tells the controller chip to turn STBY-5V on.

Power Supply (Main Power Switch Type 1) Location

MAIN POWER SWITCH LOCATION

Type 1

(Bottom Left Side viewed from rear) On Off

If the TV won’t come on, be sure to check the Main

Power Switch before assuming a failure has occurred.

This switch breaks AC to the SMPS.

LCD DV 42SL80

28 February 2010

Power Supply (SMPS) Board Layout

Hot Ground

Shock

Hazard

3.15A/250V

STBY 170V

Run 388.5V

From Hot

Gnd

SK100

AC IN

P101

Main

Power

Switch

Inverter B

POWER SUPPLY (SMPS)

42SL80 Power Supply Start Up Sequence

Inverter A

Inverter On

Starts the Inverters

24V B+ for the Inverters

Stand

By 5V

Remote or Power Button Key

MAIN BOARD

5V Q408

Switch

RL_ON

12V Video

Processing

Inv

Stand

By 5V Reg

2 6 66 8

Primary side fuse:

Stand-By 170V

Run 388.5V (Hot Gnd)

24V

Audio

12V 24V

Reg

For

Micro

12V

At point TV is in

Stand-By state.

Energy Star compliant.

Less than 1 Watt

Other Circuits

5V General

And 5V

PWM-DIM

Digital

Dimming

Manipulates

Backlights

Tuner B+

Cust Menu for

Backlight

and

Picture Content

Manipulate P-DIM

Relay On

No AC

Det in

this

model

LVDS

Video

12V

AC In

Ft IRKey

24V

INV

LVDS Panel Control

Inv On/Off

Microprocessor IC600

Also Video Processor

(RL_ON)

To Panel

3.3V, 26V, -5V, 16V

Video

Tru-Motion

LVDS Video

IC406

3.3V

IC603

Q408

PWM-DIM

CN4

CN1

P201

CN3

Main

Power

Switch

Bridge

P203

To Panel

Backlights

Power On

Power

3.3V, 26V, -5V, 16V

P205 CN101

624V CN3

CN203

INV OnSync

P400

Soft Touch Key

12V/24V

Regulators

P1000

LVDS

12V

Switch

Inverter On

P800

P801

Video

On LVDS cables

12V LVDS

T-CON Board

Voltages developed by U5

On T-CON

CN4

CN5

Reset

Generator

+5V General

PWM 2

PWM-DIM is not used

47LH85 P400 on Main Board to SMPS P201 Turn On Circuit

INV ON/OFF

PWR ON

100Ω

R414

C421

15pF

P400

11.9V

Gnd

4.9V

1.6V

PWR On

P201

ERROR

PWR

A.DIM

I-C

P-DIM

n/c

SMPS

AB12

IC600

Mstar

PWM2

PWM3

n/c

Gnd

A-DIM (Analog Dimming) Fixed Value.

H5 R775

100

GPIO137

5.2V

MAIN PWB

5.14V

Gnd

12V

24.7V

24V

Gnd

n/c n/c

E5 GPIO 134

L405

L407

+24V

C425

C427

68uF

C430

0.1uF

L402

+12V

C405

0.1uF

Q400

R425R421

R787

100Ω

R422

10KΩ

Q401

R430 0Ω

R418

3.3KΩ

GPIO 136

R774

100Ω

+5V General

RL_ON

Inverter On/Off

Q408

+5V

L417

L418

12V_TCON

L419

Q406

0.2V

0.6V

Q405

Q407

Panel Control

L411

R783

10KΩ

0.6V

+12V

R454 47KΩ

R455 47KΩ

AA13

C407

C412

100uF

5V_ST

L403

Relay On

A-DIM

P-DIM

C409

1uF

24.7V

4.3V

20K

E8 GPIO 97

R713

100ΩError Out

5.2V

R427 4.7KΩ

R426

10KΩ

+3.3V ST

R437 10KΩ

R434

0Ω

R442 0Ω

R450

560Ω

P800

T-CON

Power

On/Off

GPIO 185

Video

Processor

n/c

R726

1.2K

PWM 3

R725

1.2K

R843

0Ω

T-CON 44

P800

CN1

CN3

CN2

INVERTER A

C408

47uF

R412

0Ω

R420

0Ω

C400

22uF

0Ω

R431

0Ω

R792

100Ω

5V_ST

R449 10KΩ

IC406

+3.3V_ST

Micro B+

Multiple Pins

Panel Power

5.14V

11.9V

n/c

T-CON (UC1)

Processes P-DIM

Inverter A

Processes P-DIM

INVERTER B Scan 2

Scan 1

CN3

Duty 2

Duty 1

Inverter B

Processes P-DIM

CN203

LCD DV 42SL80

31 February 2010

Power Supply (SMPS) Board Operational Troubleshooting

Power Supply Troubleshooting

AC voltage is supplied to the Power Supply at Connector SC100. This set does not use AC Detect.

The AC input generates a Hot Ground primary power supply that runs in two states, Stand-By (170) and

Run (388.5V) measured at Fuse F1 from Hot Ground. This primary voltage develops all other voltages

that are output from the SMPS. During Stand-By, the 5 Volt Standby (5V_ST) should be present at

connector P201, Pins 7,8,9 or 10. If Missing remove AC Power and unplug Connector P201, apply AC

Power and recheck for presence of 5V_ST (5.1V to 4.7V). Loss of 5V_ST would be a SMPS Failure. If

5V_ST returns, it would be an indication of a failure on the Main Board or possibly the Front Board (IR)

assembly. Suspect a possible short circuit loading the supply. Remember to observe the Front Power

Indicating LED this may save some time. A lit LED indicates the Stand-By 5V voltage is present

and the Microprocessor is communicating with the front LED driver IC!

The Main Board sends two commands to the Power Supply Board one being PWR_ON and the other is

INV ON. These two signals are used to control the SMPS turn on sequence. First the command PWR_ON

(Pin 2) also known as POWER ON, activates the Inverter voltages 24V and the 24V and 12V lines to the

Main board. The 2nd command is INV ON (I_C) (P201 pin 20). It is the Lamp Lighting Command Signal.

If either command (PWR-ON or INV-ON) is missing it will result in a no picture symptom and the backlights

will not turn on.

These voltages can not be easily checked using the normal “Stand-Alone” Power Supply check.

This Power Supply utilizes many different voltage sensing circuits that will prevent the usual procedure.

The Stand-By 5V to the Main Board MUST BE LOADED for the SMPS to stay on.

You can not just jump the PWR_ON command from 5V_ST like it was done before. Using a simple 12V

flashlight bulb from 5V_ST to Gnd. Will supply a sufficient load to run the SMPS stand alone.

LCD DV 42SL80

32 February 2010

AC Should not be applied at any time while

adding the light bulb, resistors or while

unplugging connectors as damage to the

circuit Board may occur.

•The SMPS “MUST” be producing STBY 5V on either pin 7, 8, 9 or 10 (5V).

If 5V Standby is not being generated, the SMPS is defective and must be replaced.

There is no need to continue with the next test.

•Unplug P400 on the Main Board. Use Main Board P400 Side to insert the

light bulb and resistors.

TEST 1: LOW VOLTAGE TEST:

Step (A) Add a 12V Light Bulb (10W) between 5V_ST and Gnd. This Supplies a load on the 5V_ST line that will

allow the supply to be powered up one section at a time.

Step (B) Add a 100Ω¼ watt resistor from 5V_ST to PWR ON and the 12V and 24V Run Lines will become active.

Connector P201 Check pins 13 and 14 for 13.3V. Check pins 17 and 18 for 26.2V.

Connector P205 Check pins 1 through 5 for 26.2V.

Connector P204 Check pins 1 through 5 for 26.2V.

Remove AC power.

TEST 1 Power Supply Board Low Voltage Test

LCD DV 42SL80

33 February 2010

TEST 2: BACKLIGHT TEST:

Leave the Light Bulb and the resistor that was

added in the previous steps A and B connected.

Step (C)

Pull the Connector CN3 from the T-CON board.

Add a 100Ω¼ watt resistor from 5V Standby to I-C (Inverter On) pin 20.

Add AC Power, the Backlights should turn on.

Note: If they do not, confirm that the I-C line (Inverter On voltage) is sent out pin 12 of both P203 and P205 going to

each Inverter. If 24V and I-C are present on both Inverters, see the Inverter Section of this book.

Remove AC power and return all connectors to the correct location.

Note: Using the test above, Inverter B can not be run Stand-Alone. Inverter A can be run by removing Inverter B

CN201. But the Right side of the screen (as viewed from the front) will be brighter and the Backlights will blink.

If CN203 is removed, then Inverter A will not run.

If 24V and I-C are present on both Inverters, see the Inverter Section of this book.

TEST 2 Power Supply Board Backlight Test

LCD DV 42SL80

34 February 2010

Power Supply Connector P201 Voltage and Diode Check

Diode Check taken with meter in Diode Mode with all Connectors Removed

GndGndGndGnd15

0.72V11.9V0V12V13-14

1.6V4.9V0VPWR on2

Open4.3V0VI-C20

Open0V0VErr Out22

Openn/cn/c

2P-DIM24

Openncncnc1

GndGndGndGnd3-6

Open5.14V5.14V*5.2V7-10

GndGndGndGnd11-12

GndGndGndAGND16

0.42V24.7V0V24V17-18

ncncncnc19

Open1.67V0V

1A-DIM21

ncncncnc23

Diode

Check

Run STBYLabelPin

P201 "SMPS" to P400 "Main Board"

2 P-DIM Pin 24

is not used.

I-C

Same as

Inverter

Control

On/Off

* Stand By 5V

P201

P201 Label

Pin 1

1 A-DIM

Pin 21

Fixed Voltage

LCD DV 42SL80

35 February 2010

Power Supply P204 to Inverter A CN1 Voltage and Diode Check

Diode Check taken with meter in Diode Mode with all Connectors Removed

Open0VError14

Open3.40VPWM-DIM13

Open4.3VI-C (INV On/Off)12

Open1.6VA-DIM11

GndGndGnd6-10

0.42V24.7V24V1-5

Diode CheckRun LabelPin

P204 "SMPS" to CN1 “Inverter A"

Pin 1

There are no Stand-By voltages.

LCD DV 42SL80

36 February 2010

Power Supply P205 to Inverter B CN201 Voltage and Diode Check

Diode Check taken with meter in Diode Mode with all Connectors Removed

Open3.45VI-C (INV On/Off)12

Open1.6VA-DIM11

GndGndGnd6-10

0.42V24.7V24V1-5

Diode CheckRun LabelPin

P205 "SMPS" to CN201 “Inverter B"

There are no Stand-By voltages.

Pin 1

LCD DV 42SL80

37 February 2010

Power Supply Connector SK100 and P101 Voltage and Diode Check

Diode Check taken with meter in Diode Mode with all Connectors Removed

AC Voltage Readings Across Pins 1 and 2

for STBY and RUN.

OLN2

120Vac

Diode CheckRun STBYLabelPin

AC Voltage Readings for either pin 1 or pin

2 in STBY and RUN with one lead on

Neutral of SK101.

OLn/a2

120Vac

n/a1

Diode CheckRun STBYLabelPin

SK100 "SMPS" to AC IN P101 "SMPS" to MAIN POWER SWITCH

SK101

P100

Bottom Left of SMPS

LiveNeutral

With the Main Power Switch Closed (On) AC flows.

When Open (Off) AC open and does not flow.

AC In

To Main

Power Switch

From Main

Power Switch

LCD DV 42SL80

38 February 2010

Inverter A and B Boards

Each Inverter receives it B+ from the Switch Mode Power Supply. Inverter A

CN1 Pins 1~5 and Inverter B CN201 Pins 1~5. 24V is delivered when the

“Power On” command arrives at the SMPS.

The Backlights are turned on when the “Inverter On” command arrives. INV-

ON is sent from the Main board through the SMPS to Inverter A CN1 Pin 12.

Then Inverter A sends the On/Off (Inverter On/Off) command to Inverter B via

CN3 to CN203 pin 7.

The Backlights are manipulated by the control signal

“P-DIM (Digital Dimming)” coming from the T-CON board via CN2 pins 2 and 3

to Inverter A CN3. Then the controller chip on Inverter A sends Duty 1 and

Duty 2 to Inverter B on CN205 pins 1 and 3.

The output of 1.2Kv is sent to three sections of the backlight behind the LCD

panel. These three sections are broken up as follows: The Top and Bottom

sections are tied together, each containing 6 bulbs (total 12). The Center

section has 13 bulbs. All total 25 bulbs.

INVERTER A and B SECTION

LCD DV 42SL80

39 February 2010

Complicated and more

expensive structure

Simple structure

Lamp manufacturing process

Lamp assembly structure

Low Cost

Large number of Lamp

Drive by single inverter

EEFL Compared to CCFL (This set uses EEFL Bulbs)

Starting

Voltage

Operating

Voltage I

Starting

Voltage

and

Operating

Voltage

CCFL (Cold Cathode Fluorescent Lamp) EEFL (External Electrode Fluorescent Lamp)

Simple structure, Low price

Center 13 Bulbs

Bottom 6 Bulbs

Top 6 Bulbs

Inverter

1Inverter

Transformer

for every bulb.

More Consistent Operating VoltageWide Range for Operating Voltage

Complex structure, High price

LCD DV 42SL80

40 February 2010

Key: Long Life Time

•For CCFL, Hg gas is consumed mainly near the internal electrode

•For EEFL, longer life time is expected because there is no internal electrode consuming Hg gas

EEFL Compared to CCFL Electrodes

LCD DV 42SL80

41 February 2010

General Backlight Information

Number of lamps “25”

EEFL (External Electrode Fluorescent Lamp)

LOW COST Large number of lamps driven by a single inverter

Inverter A

Connection

board to

6 Bulbs

Connection

board to

6 Bulbs

To Backlights

Over 1.2KV

25 Bulbs

Inverter B

Connection

board to

13 Bulbs

Ties Top

board with

bottom

board

Connection

board to

6 Bulbs

Connection

board to

6 Bulbs

Connection

board to

13 Bulbs

Ties Top

board with

bottom

board

To Backlights

Over 1.2KV

LCD DV 42SL80

42 February 2010

Inverter A (Shield Removed) Layout

Ballast

Transformers

p/n EAY60750201

Includes both Inverters

CN5

To Backlights

Left Side

CN1

CN2

12A/65V

To CN3 of T-CON

To P204 of SMPS

CN3 To CN203 of Inverter B

To Top 6 bulbs

and Bottom

6 bulbs

Center 13

bulbs

Driver FETs

Driver ICs

LCD DV 42SL80

43 February 2010

Inverter B (Shield Removed) Layout

Ballast

Transformers

p/n EAY60750201

Includes both Inverters CN205

To Backlights

Right Side

CN203 F201

12A/65V

To P205 of SMPS CN201

To CN3 of Inverter A

To Top 6

bulbs and

Bottom

6 bulbs

To Center

13 bulbs

Driver FETs

Driver ICs

42SL80 Inverter A & B Layout and Component Volatages

Pin Label STBY Run Diode Check

4 GND GND GND GND

3 SCAN 2 0V 0.67V-2.4V OPEN

2 SCAN 1 0V 0.67V-2.4V OPEN

1 NC 0V 3.3V OPEN

CN2 Connector "Inverter A" to CN3 "T-CON"

Pin Label Run AC Resistance

1TO MC1

2 TO BLACK

72 Ohms

1.2Kv

CN201 Connector "Inverter B" to P205 "SMPS"

Pin Label STBY Run Resistance

12 n/c n/c 4.3V OPEN

11 Vbr-A 0V 1.6V OPEN

6-10 GND GND GND GND

1-5 OPEN

VIN 0V 24.7V

CN203 Connector "Inverter A" to CN3 "Inverter B"

Pin Label STBY Run Resistance

1 DUTY_S1 0V 0.71V-2.4V OPEN

2GND GNDGND GND

3 DUTY_S2 0V 0.71V-2.4V OPEN

4 FB_S1 0V 0.96V 2.9V

5 ON/OFF 0V 4.3V OPEN

6 STB 0V 3.2V OPEN

7 VREF 0V 1.0V OPEN

8 FB_M1 0V 1.0V 2.9V

9 SRT 0V 1.4V OPEN

10 SS 0V 2.9V OPEN

11 CT_SYNC_IN 0V 1.5V 1.7V

CN1 Connector "Inverter A" to P204 "SMPS"

Pin Label STBY Run Resistance

14 STATUS 0V 0V OPEN

13 NC 0V 0V OPEN

12 ON/OFF 0V 4.3V OPEN

11 Vbr-A 0V 1.6V OPEN

6-10 GND GND GND GND

1-5 VIN 0V 24.7V OPEN

CN3 Connector "Inverter A" to CN203 "Inverter B"

Pin Label STBY Run Resistance

11 DUTY_M1 0V 0.71V-2.4V OPEN

10 GND GND GND GND

9 DUTY_M2 0V 0.71V-2.4V OPEN

8 FB_S1 0V 0.96V 2.9V

7 ON/OFF 0V 4.3V OPEN

6 STB 0V 3.2V OPEN

5 VREF 0V 1.0V OPEN

4 FB_M1 0V 1.0V 2.9V

3 SRT 0V 1.4V OPEN

2 SS 0V 2.9V OPEN

1CT_SYNC_IN 0V 1.5V 1.7V

CN205 Connector "Inverter B" TO "LCD Panel"

Pin Label Run AC Resistance

1TO SC1

2 TO BLACK

72 Ohms

1.2Kv

21.7V

24.6V

24.8V

Q104/Q102

0.6V

21.6V

Gnd

Q106/Q103

Q3/Q6

0.73V

20.4V

GND

G24.1V

D 24.6V

S20.3V

Q2/Q4

DDDD

Inverter B

CN201

CN203

T201 T301

35V

680

65V/ 12A

Q302

Q304Q204

Q202

CN205

Q203

U201 & U301 are DC-AC

Inverter Control ICs

U201 U301

C208C243

35V

680

Q206 Q208 Q303

- + - +

Inverter A

T101

35V

680

35V

680

65V/ 12A

Q104 Q102 Q2 Q4

CN5

Q103 Q3 Q6

CN1

CN3

CN2

Q106

U101 & U1 are DC-AC

Inverter Control ICs

U101

C43

Do Not

Adjust

GG G

SSS

- +

CN5 Connector "Inverter A" TO MC1 and Black "LCD Panel"

27.0V

24.6V

23.1V

Q104/Q102

0.28V

23V

Gnd

Q106/Q103

Q3/Q6

0.3V

23.0V

GND

G26.9V

D 24.6V

S23.1V

Q2/Q4

Backlights

at 100%

Backlights

at 100%

Backlights

at 0%

21.7V

24.6V

24.8V

Q302/Q304

0.6V

21.6V

Gnd

Q306/Q303

Q203/Q206

0.73V

20.4V

GND

G24.1V

D 24.6V

S20.3V

Q202/Q204

27.0V

24.6V

23.1V

Q302/Q304

0.28V

23V

Gnd

Q306/Q303

Q203/Q206

0.3V

23.0V

GND

G26.9V

D 24.6V

S23.1V

Q202/Q204

Backlights

at 100%

Backlights

at 100%

Backlights

at 0%

LCD DV 42SL80

45 February 2010

Ballast Transformer Waveforms

All Transformers Pin 1

30V p/p 48kHz (5uSec)

29.2V p/p 48kHz (5uSec)

Both Inverters have

2 Drive Transformers.

They have the same

configuration.

Warning, secondary

is over 1.2Kv

Do Not Measure without

proper equipment.

All Transformers Pin 6

Primary

6 1 6 1

FET Drivers

Secondary

LCD DV 42SL80

46 February 2010

Ballast Transformer Noise Suppression Pads

Both Inverters have 2 Drive Transformers.

There is a rubber pad that covers both drive transformers on both A and B

Inverters. These pads reduce the vibration noise being generated from

these transformers, be sure to replace these.

Padding

Drive

Transformers

LCD DV 42SL80

47 February 2010

RF Prevention Shields behind the Inverters

Behind the Inverters are shields

Shield

Inverters A side Inverters B side

Shield

The Shield on

Inverters B side

is adhered to

the panel.

The Shield on

Inverters A side

is adhered to

the panel.

42LS80 Inverters Turn On Circuit P400 on Main Board To Power Supply P201

IC600

Mstar

INV On/Off

4.82V

P700

POWER

SUPPLY

PWR

2.86V

CN1

INV On/Off

ERR 0V

ERR

P201

P204

MAIN PWB

Relay On

Q401

Inverter On

5V_ST

Q400 E5

5V General

Stby 5V

7 8 9 10

12V

24V

21~5

24V

Reg

24V

12V

Reg

PWM-DIM

VBR-B

PWM-2

PWM-DIM (PWM Dimming) Manipulates the Backlight Brightness via Customer’s

OSD, via the video processor IC400 and by the Intelligent Sensor. Darker Picture,

Darker Backlights to facilitate improved Contrast Ratio. 0.7V ~ 2.4V Range

T-CON PWB

P800

CN1

CN3

CN2

VBR-A

PWM-0

11 21

A-DIM (Analog Dimming)

Fixed Voltage 1.6V

GPIO97

ERROR 4th time this line

goes high, power shuts off.

GPIO131

GPIO136

Hi if Lamps do not light

A-DIM

4.3V

24.7V

1.6V 1.67V

LVDS

Cable

Ballast

Driver 1 Ballast

Driver 2

Fixed

13 P-DIM not

used

13 n/c

Scan 1

Scan 2

AB12

1~5

24V

SMPS

Controler

2424

SCAN 1 and SCAN 2 are manipulated by PWM-DIM (PWM Dimming)

AB13

CN3 11 Pins Carrying On/Off, Duty, Sync and

Drive signals. Receiving Error feedback.

CN201

INVERTER

1.2kV

Out

Ballast

Driver 1

Ballast

Driver 2

48K

Drive

signals

1~5

24V

CN203

11 Pins Receiving On/Off, Duty, Sync and

Drive signals. Sending Error feedback.

P205

1~5

24.7V

Output

FETs

Output

Transformers

1.2kV

Out

48K

Drive

signals

Output

FETs

Output

Transformers

For Circuit Details, see

P400 ON MAIN PWB TO

SMPS P201 TURN ON

CIRCUIT

VIN

On/Off

INVERTER

n/c

UC1

LCD DV 42SL80

49 February 2010

Power Supply Backlight Drive Signal Effects

PWM-DIM

manipulates

the Burst

Triangle

Oscillator in

the ballast

drive IC.

A-DIM also

manipulates

the Burst

Triangle

Oscillator

But it is not

used.

Note:

Backlights will

attempt to fire 4

times. During these

attempts, the Error

line will change

from 5V to 0V.

0V when lamp tries

to fire or is lit.

5V when the lamps

are not lit.

After 4 attempts, if

the Error Out line

returns to 5V, this

tells the Micro to

turn the set off.

LCD DV 42SL80

50 February 2010

Inverter A Connector CN1 and CN2 Voltage and Diode Check

Diode Check taken with meter in Diode Mode with all Connectors Removed

Open24.7VVIN1-5

Open1.6VVRB-A11

Open4.3VOn/Off12

Open0Vn/c13

Open0VStatus14

GndGndGnd6-10

Diode CheckRun LabelPin

CN1 “Inverter A" to P203 "SMPS"

There are no Stand-By voltages.

Open3.3Vn/c4

Open*0.67V~2.4VScan 23

Open*0.67V~2.4VScan 12

GndGndGnd1

Diode CheckRun LabelPin

CN2 “Inverter A" to CN3 “T-CON"

Pins 2/3

(Digital Dimming)

Can vary according to

the brightness level of

the video signal and the

OSD Backlight setting.

0.67V 0% to 2.4V

100%. Output from the

Video Processing chip

IC100 (Mstar) through

T-CON.

Pin 13 PDIM

(Digital Dimming)

This pin is not used.

CN1

CN2

LCD DV 42SL80

51 February 2010

Inverter A Connector CN3 Voltage and Diode Check

Diode Check taken with meter in Diode Mode with all Connectors Removed

Open2.9VSS2

Open1.4VSRT3

2.9V1.0VOn/Off4

Open1.0VVREF5

Open3.2VSTB6

1.7V1.5VCT-SYNC-IN1

2.9V0.96VFB_S18

Open*0.71V~2.4VDUTY_M29

GndGndGnd10

Open*0.71V~2.4VDUTY_M111

Open4.3ON/OFF7

Diode CheckRun LabelPin

CN3 “Inverter A" to P203 “Inverter B"

There are no Stand-By voltages.

Varies with PDIM

CN3

Varies with PDIM

LCD DV 42SL80

52 February 2010

Open24.7VVIN1-5

GndGndGnd6-10

Open1.6VN/C11-12

Diode CheckRun LabelPin

CN201 “Inverter B" to P205 "SMPS"

Inverter B Connector CN201 Voltage and Diode Check

Diode Check taken with meter in Diode Mode with all Connectors Removed

There are no Stand-By voltages.

Pin 11 and 12

are not used.

CN201

F201

24.7V Fuse

LCD DV 42SL80

53 February 2010

Inverter B Connector CN203 Voltage and Diode Check

Diode Check taken with meter in Diode Mode with all Connectors Removed

Open2.9VSS10

Open1.4VSRT9

2.9V1.0VFB_M18

Open1.0VVREF7

Open3.2VSTB6

Open1.5VCT-SYNC-IN11

2.9V0.96VFB_S14

Open*0.71V~2.4VDUTY_S23

GndGndGnd2

Open*0.71V~2.4VDUTY_S11

Open4.3ON/OFF5

Diode CheckRun LabelPin

CN203 “Inverter B" to CN3 “Inverter A"

There are no Stand-By voltages.

Varies with PDIM

CN203

Varies with PDIM

Pins 1/3 Duty

(Digital Dimming)

Can vary according to

the brightness level of

the video signal and the

OSD Backlight setting.

0.67V 0% to 2.4V

100%. Output from the

Video Processing chip

IC100 (Mstar) through

T-CON.

LCD DV 42SL80

54 February 2010

LCD Controller Board

The T-CON IC UC1 receives from the Main Boards LVDS Video Signals at CN1 and CN2.

This is a Dual 12 Bit (24 pin) LVDS Video Signal which it processes into TFT Drive Signals

which are delivered through connectors CN4 and CN5 to the LCD TFT Panel.

T-CON B+: 12V is supplied to the T-Con Board on connector CN1 from the Main Board

P800 easily measured at fuse F1, (3A and 125V).

There is a DC to DC converter (U5) that creates;

(16V Measured at VDD). (26V Measured at pin 8 of U5).

(3.3V Measured at VCC). (-5V Measured at D9 top right leg).

These Voltages can also be measured at the ribbon connectors delivering signals to the

TFT panel

(CN4 26V pin 4, -5V pin 2, 3.3V pins 53, 54 and 16V pins 56, 57 and 58).

(CN5 26V pin 57, -5V pin 59, 3.3V pins 7, 8 and 16V pins 3,4 and 5).

See the 11X17 Foldout (Interconnect Diagram) for more details.

In the set the T-CON also receives the P-DIM voltage from the Main board on CN1 pin 8.

Then the Controller UC1 outputs P-DIM control signals now called Scan 1 and Scan 2 on

the CN3 connector, pins 2 and 3 to Inverter A CN2.

T-

-CON (TFT DRIVE) SECTION

CON (TFT DRIVE) SECTION

T-CON (TFT Drive) with (Shield Removed) Components Identified

Warning:

T-Con PWB under shield. Be sure to reinsert screws before operating set with shield removed.

p/n EAT60667401

1) 6.9V

2) 13.7V

3) 15.7V

4) 13.7V

5) 13.0V

6) 12.0V

7) 10.9V

8) Gnd

9) 16.0V

10) 10.1V

11) 8.2V

12) 7.7V

13) 3.3V

14) 3.3V

15) 3.3V

16) Gnd

17) Gnd

18) Gnd

19) 5.8V

20) 5.0V

21) 3.9V

22) 2.9V

23) 6.0V

24) Gnd

25) 2.2V

26) 0.3V

27) 2.2V

28) 6.9V

TO TFT MODULE

UC1

FL3

1) Gnd

2) 1.8V

3) 3.3V

TO TFT MODULE

T-CON BOARD

(TFT Driver)

Gnd Protect

U11

U12

U10

(VGL) Pin 2

(VGH_M) Pin 4

(VDD_LCM) Pin 56,57,58

(VCC) Pin 53,54 26V

16V -5V

3.3V

26V 16V-5V 3.3V

2.78V

U13

FL2

Gnd Protect

D10

3.3V

20.5V

14.25V

-2.4V

R704

R705

R706

3.3V

26V

27V

C744

R721

Gnd

-5V

VCC

(CN1) Pin 48-51

F1 (12V)

125V / 3A

CN1 CN2

U5 B+ 12V

16V

VGH_M

16V

VGL

12V

3.3V

CN4

CN3

C308

C307

C306

C305

16.3V 3.3V

C304

C303

C302

C301

16.3V3.3V

CN5

(VDD_LCM) Pin 3,4,5

(VCC) Pin 7,8

(VGL) Pin 59

(VGH_M) Pin 57

Gnd

3.8V P/P

9.97Mhz

VDD

1~4) Gnd

5) 0V

6) 3.3V

7) 3.3V

8) 3.3V

LCD DV 42SL80

56 February 2010

T-

-CON (TFT Drive) Board Checks

CON (TFT Drive) Board Checks

T-CON Board (Locations)

1.8V

3.3V

Gnd

U11

Check the Regulator for

Correct Voltage

Check Fuse F1 for 12V

Voltage supplied from CN1

Pins 48, 49, 50, and 51.

CN1

Check

Fuse

F1 (12V)

1~4) Gnd

5) 0V

6) 3.3V

7) 3.3V

8) 3.3V

U10

LCD DV 42SL80

57 February 2010

T-

-CON (TFT Drive) Panel Voltage Development Checks

CON (TFT Drive) Panel Voltage Development Checks

The development for the

voltages on the CN4 and CN5

connectors are shown here.

This is an excerpt from the

Interconnect diagram.

Panel voltages are outlined

in the rounded cornered

boxes.

LCD DV 42SL80

58 February 2010

T-

-CON Board Connector CN1 to Main Board Voltage and Diode Check

CON Board Connector CN1 to Main Board Voltage and Diode Check

Diode Check taken with meter in Diode

Mode with all Connectors Removed

CN1 CONNECTOR "T-CON Board“ to P800 "Main"

*Pin 8 PWM-DIM 3.15V (Max 100%) to 0.6V (Min 0%)

Customer’s Menu Backlight setting.

1.1V1.3VURSA_A+2

1.1V1.3VURSA_A-2

Open0V

N/C

1.1V1.3VURSA_B+0

1.1V1.3VURSA_B-0

1.1V1.3VURSA_B+1

1.1V1.3VURSA_B-1

1.1V1.3VURSA_B+2

1.1V1.3VURSA_B-2

1.1V1.2VURSA_BCK+

1.1V1.1VURSA_BCK-

1.1V1.3VURSA_B+3

1.1V1.3VURSA_B-3

1.1V1.3VURSA_B+4

1.1V1.3VURSA_B-4

3.18V12.06V12V T-CON48-51

Diode CheckRunLabelPin

Open0V

N/C

1.3V*2.7V

PWM-DIM

Open0V

N/C

1.75V0.6VOPC_EN

Open0V

N/C

1.1V1.3VURSA_A+0

1.1V1.3VURSA_A-0

1.1V1.3VURSA_A+1

1.1V1.3VURSA_A-1

1.1V1.2VURSA_A+2

1.1V1.1VURSA_A-2

1.1V1.1VURSA_ACK+

1.1V1.2VURSA_ACK-

1.1V1.3VURSA_A+3

1.1V1.3VURSA_A-3

Diode CheckRunLabelPin

See arrow on the T-CON

board CN1 indicating pin 1

Pins 2, 3, 4, 5, 6 and 47

are all no connection.

Pins 1, 18, 21, 26, 34, 37,

42, 43, 44, 45 and 46 are

all ground.

CN1

Text in Blue are

LVDS video

signals.

LCD DV 42SL80

59 February 2010

T-

-CON Board Connector CN2 to the Main Board (Voltage and Diode Ch

CON Board Connector CN2 to the Main Board (Voltage and Diode Check)

eck)

Diode Mode values taken with all Connectors Removed

CN2 “T-CON“ to P801 CONNECTOR "Main"

Open1.3VURSA-C+320

Open1.2VURSA-C-321

Open1.13VURSA-C+422

Open1.18VURSA-C-423

GndGndGnd24

GndGndGnd25

Diode TestRunLabelPin

GndGndGnd19

Open1.23VURSA-CCK-18

Open1.23VURSA-CCK+17

GndGndGnd16

Open1.2VURSA-C-215

Open1.3VURSA-C+214

Open1.2VURSA-C-113

Open1.3VURSA-C+112

Open1.2VURSA-C-O11

Open1.28VURSA-C+010

n/cn/cn/c1-9

Diode TestRunLabelPin

GndGndGnd40-41

Open1.15VURSA-D-439

Open1.4VURSA-D+438

Open1.25VURSA-D-337

Open1.3VURSA-D+336

GndGndGnd35

Open1.29VURSA-DCK-34

Open1.23VURSA-DCK+33

GndGndGnd32

Open1.2VURSA-D-231

Open1.3VURSA-D+230

Open1.3VURSA-D-129

Open1.29VURSA-D+128

Open1.25VURSA-D-027

Open1.29VURSA-D+026

See arrow on the

T-CON board CN1

indicating pin 1

CN2

Text in Blue are

LVDS video

signals.

LCD DV 42SL80

60 February 2010

T-

-CON Board Connector CN3 to Inverter A (Voltage and Diode Check)

CON Board Connector CN3 to Inverter A (Voltage and Diode Check)

Diode Mode values taken with

all Connectors Removed

CN3 “T-CON“ to CN2 “Inverter A"

Open0.67V~2.4VSCAN 23

Diode TestRunLabelPin

GndGndGnd4

Open0.67V~2.4VSCAN 12

n/cn/cn/c1

See arrow on the

T-CON board CN3

indicating pin 1

CN3

Pins 2 SCAN 1 and 3 SCAN 2 (Digital Dimming)

Can vary according to the brightness level of the

video signal and the OSD Backlight setting.

0.67V 0% to 2.4V 100%.

P-DIM Output from the Video Processing chip IC100

(Mstar) and input on CN1 pin 8 T-CON.

LCD DV 42SL80

61 February 2010

MAIN BOARD SECTION

The Main board receives its operational B+ from the Power Supply via P400.

There are two LVDS cable feeds that go to the T-CON (TFT Driver) section. These carry the Dual 12

bit LVDS Video signals and the TruMotion 60Hz Dual 12 bit LVDS. These signals have already been

prepared for the T-CON board. The Main board also includes the Tuner, Audio and Audio/Video

inputs and selection circuits.

STAND-BY

•STBY 5V pins 7~10

The Main board also develops several B+ sources on the board.

LVDS

•LVDS 12V AUDIO

•3.3V

•1.8V_AMP

Mstar IC600 Video and Micro Processors

•1.2V

IC3502 Tru-Motion IC.

•1.26V_MEMC, 1.8V_MEMC,

1.8V_DDR, and 3.3V

RUN

•12V pins 13 and 14

•24V pins 17 and 18.

TUNER and VSB CIRCUIT

•9V

•5V TU

•3.3V_DVDD_PVSB

•1.2V_DVDD_PVSB

•3.3V_DVDD_PVSB

STAND-BY VOLTAGES

•3.3V_ST

GENERAL

•5V_General

•5V_EXT

Input Voltages from SMPS.

Digital Video Demodulator/Decoder

Progressive Vestal Side Band

(Dif + / Dif -)

IF_P / IF_N

Tuner Developed from 9V above

Motion

Estimation

Motion

Compensation

Amplifier (Audio)

Voltage_Stand By

Stand By

Double Data Rate-Synchronous RAM Memory

For Audio Amplification

(Converted to 24V_Amp)

For Tuner Voltage (Dropped to 5V)

and output (Switched) for T-CON

For all other regulators except 12V/24V

and output to Ft. IR

For Microprocessor and output to Ft. IR

For Video Processing / DDRs

For Tuner Demodulator Low Voltage

Development

For Tuner B+ Developed from 12V Input

Not generated, but switched from the

12V arriving from the SMPS.

LCD DV 42SL80

62 February 2010

Additional Main Board Information

Input Signal Processing

IC600 is the main Microprocessor and the main Signal Processor.

The Main board is responsible for :

• ATSC, NTSC, and QAM reception and processing

• RS 232 service only Port (software upgrades and home theater environment).

•Wired Remote Port

• (2) Component Input Y, Pr, Pb and Audio L R

• (3) HDMI Inputs (back) (1) HDMI (Side Input)

• RGB PC and (PC Audio)

• USB (software upgrades using flash drive). USB located on the Side.

• AV Composite (1 Rear and 1 Side Input)

• SIF and SAP Output Signals

• Dual 12 Bit (24 pin) LVDS to the T-CON Board via P800 and P801.

• Including 12V T-CON.

• Audio output signals to the Speakers P300.

• Digital Audio Output Coaxial and Optical Always active, (Note: HDMI converts to Stereo)

• ON OFF Controls to the SMPS turning on low voltage generation and Backlights.

• Backlight intensity control signal (Digital Dimming) P-DIM sent to the T-CON board.

LCD DV 42SL80

63 February 2010

Main Board Layout

VIDEO PROCESSOR

IC600 RUNS HOT,

THIS IS NORMAL.

P700 To

SMPS

P1000

To Front IR

Board

Assembly

T-CON Board

To Speakers

Look carefully on top

and behind the Video

Processor IC for

Chocolate

(Heat Transfer)

material.

Be sure to transfer to

new Board if replaced.

P300

IC600

Microprocessor

and

Video Processor

IC801

Tru-Motion

P800 P801T-CON Board

IC1200

Audio Amp

DDR

P800

IC801

Tru-

Motion

P801

IC801 Operates at

high temperature

X800

25Mhz

Q408

IC300

Q1000

IC604

IC901

IC900

IC1

X600

12Mhz

IC600

Micro/Video

Processor

Mstar

IC404

IC504SW600

IC1200

L304

P1000

Q500

TU500 Tuner

TDVW-H103F

X500

25Mhz

P803

N/A

IC502

12V LVDS

Pins 1~4

P300

42LS80

MAIN BOARD

42SL80

Main Board

(Front Side)

Component

Layout

42SL80

Main Board

(Front Side)

Component

Layout

P100

L305

IC301

P400

IC2

IC500

D500

IC406

NAND

FLASH

IC400

IC605

IC602

A2D1003

R-

R+

L-

L+

Q406

IC600

Mstar

DDR

Audio

PC RS232

HDMI 1

HDMI 2

HDMI 3

Pr Pb

YPrPb Audio

Video LR

L406

L412

L422

L424

(1)

(19) Analog Video

(4) Tuner 5V_TU

(8) Data

(9) Clock

(12) Dig DIF+

(13) Dig DIF-

(16) SIF

HDMI

USB

42SL80 Main (Front Side) Component Voltages

IC300 +1.8V AMP IC406 +3.3V_ST IC605 Reset Gen Q500 Tuner Video IC403 +1.6V_MEMC

Pin Regulator Pin Regulator Pin for Power_Det Pin Buffer Pin Regulator

[1] Gnd [1] 0V [1] Gnd B 1.7V [1] 0V

[2] 1.8V [2] 3.3V [2] 3.5V C 0V [2] 0.8V

[3] 3.3V [3] 5.0V [3] 3.3V E 2.3V [3] 1.2V

[4] 1.2V

IC400 +1.8V_DDR IC500 9V Reg Q406 5V Switch Q1000 Moving LED [5] 1.8V

Pin Regulator Pin to IC501 Tuner 5V Pin Control Pin Inverter [6] 5.0V

[1] n/c [1] 12V B 0.6V B 0V [7] 1.2V

[2] 3.2V [2] Gnd C 0V C 3.3V [8] 5.0V

[3] 3.2V [3] 8.9V E Gnd E Gnd

[4] n/c

[5] n/c IC504 +3.3V_PVSB Q408 +5V/12VLVDS D500 Speed Up Reset

[6] 1.8V Pin Regulator Pin Switch Pin IC502

[7] 0.8V [1] 4.94V [1] 5.1V C 3.4V

[8] Gnd [2] 4.94V [2] 0.29V A 3.38V

[3] Gnd [3] 11.9V

IC404 +1.8V_MEMC [4] 3.4V [4] 5.99V D1003 Moving LED

Pin Regulator [5] 1.25V [5] 11.98V Pin Routing

[1] 0.8V [6] 11.98V A1 0V

[2] Gnd IC602 HDCP [7] 5.06V C 0.1V

[3] 4.92V Pin EEPROM [8] 5.06V A2 0V

[4] 6.5V [1] Gnd

[5] 4.8V [2] Gnd

[6] 1.8V [3] 5.0V

[7] 1.8V [4] Gnd

[8] 4.8V [5] 3.3V

[6] 3.3V

[7] 5.0V

[8] 5.0V

42SL80

Main Board

(Back Side)

Component Layout

42SL80

Main Board

(Back Side)

Component Layout

TUNER TU500

TDVW-H103F

IC100

A2A1

42SL80 MAIN BOARD

(Back View)

IC501

IC503

IC102

IC504

IC1000

IC601

Q600

IC800

IC606

IC401

IC402

Q407

Q405

Q605

Q400

Q604

Q401

IC603

BQ603

Q602

D600

BQ300

A2A1

D200

Q200

A2A1 D129

IC101

Q101

(1)

(19) Analog Video

(4) Tuner 5V_TU

(8) Data

(9) Clock

(12) Dig DIF+

(13) Dig DIF-

(16) SIF E

BQ501

42SL80 Main (Back Side) Component Voltages

IC100 RS232 IC402 +3.3V_MEMC IC601 Serial Flash Q101 IR RS232 Q501 Tuner SIF

Pin Rx/Tx Pin Regulator Pin for Boot Pin Buffer Pin Buffer

[1] 3.3V [1] [1] 0.04V B 0.634V B 2.4V

[2] 5.56V [2] Gnd [2] 3.2V C 0V C 0V

[3] 0.02V [3] 4.98V [3] 2.5V E 0V E 3.0V

[4] 0.03V [4] 7.6V [4] 0V

[5] 5.5V [5] 4.9V [5] 0V Q200 HDMI CEC Q600 Write Protect

[6] 5.5V [6] 3.3V [6] 0V Pin Pin for IC601

[7] 5.5V [7] 3.3V [7] 3.2V [1] 3.2V B 0V

[8] 0V [8] 0V [8] 3.2V [2] 3.2V C 2.5V

[9] 3.29V [3] 0V E Gnd

[10] 3.24V IC405 +5V EXT IC606 Micro IC600 [4] 0V

[11] n/c Pin Regulator Pin EEPROM [5] 0V Q602 S5/S6 Reset

[12] 3.31V [1] 0.8V [1] Gnd [6] 3.16V Pin Switch for Mstar

[13] 0V [2] Gnd [2] Gnd B 0V

[14] 5.5V [3] 12V [3] Gnd Q300 Audio Mute C 3.28V

[15] Gnd [4] 9.6V [4] Gnd Pin Switch E 0V

[16] 3.29V [5] 5V [5] 3.24V B 0.62V

[6] 4.97V [6] 3.24V C 0.01V Q603 Power_On_

IC101 SPIF Optical [7] 4.97V [7] 0V E Gnd Pin Delay Switch

Pin Audio [8] 1.9V [8] 3.24V B 0V

[1] 0.03V Q400 PWR On/Off C 0.04V

[2] 0V IC501 +5V_TU IC800 SPI Flash IC801 Pin Switch E Gnd

[3] 0V Pin for Tuner Pin Memory B 2.9V

[4] 0V [1] 8.92V [1] 0V C 5V Q604 Power_Det

[5] 0V [2] 1.88V [2] 0.8V E 5V Pin Switch

[3] 5.04V [3] 3.2V B 0V

IC102 RGB [4] 0V [4] 0V Q401 INV_ON C 3.3V

Pin EEPROM [5] Gnd [5] 0V Pin Inverter E Gnd

[1] Gnd [6] 0.09V B 0.05V

[2] Gnd IC503 +1.2V_PVSB [7] 3.2V C 4.35V Q605 Power_Det

[3] Gnd Pin Regulator [8] 3.2V E Gnd Pin +12V Side

[4] Gnd [1] 0V B 0.65V

[5] 3.3V [2] 3.3V IC1000 USB +5V Q405 12V LVDS C 0.0V

[6] 3.3V [3] 3.4V Pin Switch Pin Switch Control E Gnd

[7] 3.18V [4] 0V [1] 4.95V B 0.05V

[8] 0V [5] 0V [2] Gnd C 0.65V D129 5V Routing

[6] 1.2V [3] 3.21V E Gnd Pin for IC1200

IC401 +1.26V_VDDC [7] 0.8V [4] 4.95V A1 0.03V

Pin Regulator [8] 0V [5] 0V Q407 12V LVDS C 4.5V

[1] [6] 4.95V Pin Source A2 5.1V

[2] Gnd IC504 +1.26V_PVSB B 0.65V

[3] 5.0V Pin Regulator IC603 Reset Gen C 0.0V D200 Shunt for

[4] 6.0V [1] 0.8V Pin for IC600 E Gnd Pin Q200

[5] 4.9V [2] 0V [1] 0V A1 0V

[6] 0V [3] 11.8V [2] 0V C 3.1V

[7] 0V [4] 9.6V [3] 3.3V A2 3.2V

[8] 3.2V [5] 5.0V

[6] 5.0V D600 Audio Mute

[7] 5.0V Pin Routing

[8] 0.9V A1 0.01V

C 2.7V

A2 3.29V

WARNING

Measure Pin 1

with O-scope

ONLY

WARNING

Measure Pin 1

with O-scope

ONLY

LCD DV 42SL80

68 February 2010

Main Board X600 and X800 Check

X800

Location

X600

Location

2.28Vp/p

12Mhz

Set on or off

IC600 Microprocessor Crystal

MAIN Board

2.8Vp/p

12Mhz

X800

Crystal for TruMotion IC801

Only when set is on

X600

1.62V

1.58V

1.6V

1.58V

LCD DV 42SL80

69 February 2010

Main Board Tuner with Shield Off (Pin ID)

LCD DV 42SL80

70 February 2010

MAIN Board

Tuner Location

Main Board Tuner Video and SIF Output Check

450mVp/p

Pin 16 “SIF” Signal

USING COLOR BAR SIGNAL INPUT Pin 12 and Pin 13

“Dig IF” Signal

Note: “Dig IF” Signal only

when receiving a Digital

Channel.

700mVp/p

Pin 1

Pin 19

“Video”

Signal

2.24Vp/p

Note: “Video Out” Signal only when

receiving an analog Channel.

LCD DV 42SL80

71 February 2010

Main Board Tuner Clock and Data Lines

Pin 8 SDA

100uS1V per/div 5V p/p

Pin 9 SCL

100uS1V per/div 5V p/p

Note:

SCL and SDA only active

during an actual

Channel Change.

LCD DV 42SL80

72 February 2010

MAIN Board

Main Board LVDS P800 Video Output Check

P800

Location

To confirm that the Main Board is outputting Picture Content signals, check P800 (LVDS) cable for

output. Check pins 11-14,16-17, 19-24, 27-30, 32-33 and 35-40. Pins 35-36 carry the clock for TA

and 19-20 carry the clock for TB. These signals vary from each other, but looking for signals like

the ones shown below on any of these pins will confirm the output of video content. This signal is

using standard SMTE Color Bar output from a generator as the input source.

Pin 1

Pin 39

This is just a sample of two pins on the LVDS.

There are 20 pins on P801 carrying video.

2uS

500nS

2uS

500nS

Pin 51

Pin 1, 2, 3, 4 (LVDS 12V)

P800

Pin 11

LCD DV 42SL80

73 February 2010

Main Board Connector P400 to Power Supply Voltage and Diode Chec

Main Board Connector P400 to Power Supply Voltage and Diode Check

Diode Check taken with meter in Diode Mode with all Connectors Removed

1(A-DIM) Pin 21 Fixed and not used 2 PDIM Pin 24 is open on the Main Board

P400 1

ncncncnc23

GndGndGndGnd11-12

GndGndGndGnd3-6

ncncncnc1

Open0V0V

2PDIM24

Open0V0VERROR22

Open1.8V0V

1A-DIM21

Open4.3V0VINV.ON20

ncncncnc19

Open24.7V0V24V17-18

GndGndGndGnd15-16

2.1V11.9V0V12V13-14

1.1V5.14V5.14V5.2V7-10

2.7V4.9V0VPWR on2

Diode

Check

Run STBYLabelPin

P400 “Main” to P201 “SMPS”

Stand By

LCD DV 42SL80

74 February 2010

Main Board LVDS Connector P800 Pin Identification

12V for

T-CON

Board

Pin 44 PDIM (Digital Dimming) Can vary according to the brightness level

of the video signal and the OSD Backlight setting. 0.6V 0% to 3.3V 100%.

Output from the Video Processing chip IC100 (Mstar).

Video

10bit TA or

10bit TB

Resolution

Video

51 1

P800

Video

Clock

LCD DV 42SL80

75 February 2010

Main Board Connector P800 to T

Main Board Connector P800 to T-

-CON Voltage and Diode Check

CON Voltage and Diode Check

Diode Check taken with meter in Diode Mode with all Connectors Removed

P800 "Main" CONNECTOR to CN1 "T-CON Board“

*Pin 44 PWM-DIM 3.2V (Max 100%) to

0.6V (Min 0%) Customer’s Menu Backlight setting.

The T-CON then routes P-DIM to the Ballast.

Pins 6,7,8,9,10, 15, 18, 26,

31, 34, and 51 are all

ground.

1.1V1.3VURSA_A-2

N/CN/CN/C

1.1V1.3VURSA_B+0

1.1V1.3VURSA_B-0

1.1V1.3VURSA_B+1

1.1V1.3VURSA_B-1

1.1V1.3VURSA_B+2

1.1V1.3VURSA_B-2

1.1V1.2VURSA_BCK+

1.1V1.1VURSA_BCK-

1.1V1.3VURSA_B+3

1.1V1.3VURSA_B-3

1.1V1.3VURSA_B+4

1.1V1.3VURSA_B-4

3.18V12.06V12V T-CON

1~4

Diode CheckRunLabelPin

N/CN/C

N/C

1.3V*3.2V

PWM-DIM

N/CN/CN/C

1.75V0.6VOPC_EN

N/CN/CN/C

1.1V1.3VURSA_A+0

1.1V1.3VURSA_A-0

1.1V1.3VURSA_A+1

1.1V1.3VURSA_A-1

1.1V1.2VURSA_A+2

1.1V1.1VURSA_A-2

1.1V1.1VURSA_ACK+

1.1V1.2VURSA_ACK-

1.1V1.3VURSA_A+3

1.1V1.3VURSA_A-3

1.1V1.3VURSA_A+2

Diode CheckRunLabelPin

Pins 5, 41, 43, 46, 47, 48,

49 and 50 are all no

connection.

(Pin 1) is on the right

Text in Blue are

LVDS video

signals.

LCD DV 42SL80

76 February 2010

Main Board Connector P801 to the T

Main Board Connector P801 to the T-

-CON Board Voltage and Diode Check

CON Board Voltage and Diode Check

Diode Mode values taken with all Connectors Removed

P801 CONNECTOR "Main" to CN2 “T-CON"

GndGndGnd18

GndGndGnd17

Open1.29VURSA-D+016

Open1.25VURSA-D-015

Open1.29VURSA-D+114

Open1.3VURSA-D-113

Open1.3VURSA-D+212

Open1.2VURSA-D-211

GndGndGnd10

Open1.23VURSA-DCK+9

Open1.29VURSA-DCK-8

GndGndGnd7

Open1.3VURSA-D+36

Open1.25VURSA-D-35

Open1.4VURSA-D+44

Open1.15VURSA-D-43

GndGndGnd1-2

Diode TestRunLabelPin

n/cn/cn/c34-41

n/cn/cn/c33

Open1.28VURSA-C+032

Open1.2VURSA-C-O31

Open1.3VURSA-C+130

Open1.2VURSA-C-129

Open1.3VURSA-C+228

Open1.2VURSA-C-227

GndGndGnd26

Open1.23VURSA-CCK+25

Open1.23VURSA-CCK-24

GndGndGnd23

Open1.3VURSA-C+322

Open1.2VURSA-C-321

Open1.13VURSA-C+420

Open1.18VURSA-C-419

Diode TestRunLabelPin

(Pin 1) is on the right

Text in Blue

are LVDS

video

signals.

LCD DV 42SL80

77 February 2010

Main Board Connector P1000 to (Ft. IR/LED Control) Voltage and

Main Board Connector P1000 to (Ft. IR/LED Control) Voltage and Diode Check

Diode Check

Diode Check taken with meter in Diode Mode with all Connectors Removed

P1000 CONNECTOR "MAIN Board" to P100 "Front IR / LED Board Assy"

Open3.29V0VPWR_ON12

0.67V3.31V3.31V3.3V_ST11

GndGndGndGnd10

Open4.18V4.18VIR9

GndGndGndWarm_ST8

GndGndGndGnd7

1.1V5.1V5.1V5V ST6

1.3V3.26V3.26VKey25

1.0V3.26V3.26VKey14

GndGndGndGnd3

1.6V3.2V0VSDA2

1.6V3.2V0VSCL1

Diode CheckRun STBYLabelPin

P1000

LCD DV 42SL80

78 February 2010

Main Board Connector P300 to Speakers Voltage and Diode Check

Diode Check taken with meter in Diode Mode with all Connectors Removed

SPK-L(+)

SPK-L(-)

SPK-R(+)

SPK-R(-)

LABEL

2.63V12.0V0V4

2.63V12.0V0V3

2.63V12.0V0V2

2.63V12.0V0V1

Diode CheckRunSBYPin

P300 CONNECTOR "Main" to "Speakers"

Use speaker out to test for defective Audio Amp IC301

1IC301

LCD DV 42SL80

79 February 2010

Side A/V Board Connector P100 to Main P101 Voltage and Diode Che

Side A/V Board Connector P100 to Main P101 Voltage and Diode Check

Diode Check taken with meter in Diode Mode

with all Connectors Removed

P101 Connector “Side A/V IN Board" to P100 "Main"

Main

P101

P100

GndGndGndGnd8

Open0V0VAV_R_IN7

GndGndGndGnd6

Open0V0VAV_L_IN5

GndGndGndGnd4

Open0V0VAV_DET3

Open0V0VCVBS_IN2

GndGndGndGnd1

Diode

Check

RunSTBYLabelPin

Side AV Board

GndGndGndGnd1

0.07V0V0VCVBS_IN2

Open0V0VAV_DET3

GndGndGndGnd4

Open0V0VAV_L_IN5

GndGndGndGnd6

Open0V0VAV_R_IN7

GndGndGndGnd8

Diode

Check

RunSTBYLabelPin

P100 Connector “Main" to P100 " Side A/V IN Board"

Main

LCD DV 42SL80

80 February 2010

FRONT IR SECTION

The Front IR board contains the Infrared receiver and the Intelligent Sensor.

This board receives its B+ (STBY5V) from the Main Board. It also has connections to the side Key

board. The 3.3V pull up for the Soft Touch Keys is routed from the Main board through the Front IR

board to the Soft Touch Key board.

The Front Power LEDs are now on the Soft Touch Key Board section and pulsate incrementally as the

set turns on and decrease as the set turns off. This is accomplished using an LED driver IC which

communicates with the Main board via Clock and Data lines.

There are several Zener diodes on the board as well and since it receives STAND-BY 5V (STBY 5V) it

could make the Power Supply or the Main board appear to be defective if a short was introduced to the

stand by line.

IR Board

Soft Touch

Key and LED

Board

LCD DV 42SL80

81 February 2010

Front Board Assembly (IR and Power LED) Layout (Front and Back V

Front Board Assembly (IR and Power LED) Layout (Front and Back View)

iew)

To Main Board

To Main

Board

To Soft Touch

Key Board

Note: STBY5V is routed to this board.

Be aware of a possibility for a short.

P100

Main Power SW Removed

IR Sensor Intelligent

Sensor

IC101

IR Sensor

P100

P101

p/n: EBR63322103

LCD DV 42SL80

82 February 2010

Front Board Assembly Component Check

D100 5.14V both sides

0V 5.14V

Q100

D100

5V 4.18VGnd

IC101

LCD DV 42SL80

83 February 2010

Front Connector P100 to Main Voltage and Diode Check

Diode Check taken with meter in Diode Mode with all

Connectors Removed

P100 Connector “IR Board“

to "MAIN Board" P1000 P100

Open3.2V0VSCL1

Open3.2V0VSDA2

GndGndGndGnd3

Open3.26V3.26VKey14

Open3.26V3.26VKey25

2.6V5.1V5.1V5V ST6

GndGndGndGnd7

GndGndGndGnd8

2.6V4.18V4.18VIR9

GndGndGndGnd10

Open3.31V3.31V3.3V_ST11

Open3.29V0VPOWER_ON12

Diode CheckRun STBYLabelPin

LCD DV 42SL80

84 February 2010

Front Connector P101 to Soft Key Board Voltage and Diode Check

Diode Check taken with meter in Diode Mode with all

Connectors Removed

P101 Connector “IR Board“ to

“Soft Touch Key Board" J2

P101

0.8V0V0VPWM BUZZ8

Open3.26V3.26VKey27

Open3.26V3.26VKey16

Open0V0VReset5

Open5.1V5.1V5V ST4

GndGndGndGnd3

Open3.31V3.31VSDA2

Open3.29V0VSCL1

Diode CheckRun STBYLabelPin

LCD DV 42SL80

85 February 2010

SOFT TOUCH KEY BOARD SECTION

To Ft. IR

Glue

Note: The Soft Touch Key Board is Glued into place.

p/n: EBR63609903

LCD DV 42SL80

86 February 2010

Soft Touch Key Assembly J2 Information

P101 Connector “IR Board“ to

“Soft Touch Key Board" J2

1.3V0V0VPWM BUZZ8

1.5V3.26V3.26VKey27

1.5V3.26V3.26VKey16

Open0V0VReset5

1.6V5.1V5.1V5V ST4

GndGndGndGnd3

1.5V3.31V3.31VSDA2

1.5V3.29V0VSCL1

Diode CheckRun STBYLabelPin

LCD DV 42SL80

87 February 2010

INVISIBLE SPEAKER SYSTEM SECTION

The 42SL80 contains the Invisible Speaker system.

The Full Range Speakers point downward, so there are no front viewable

speaker grills or air ports.

Invisible Speaker System Overview (Full Range Speakers)

Reading

across speaker

wires, 8.2 ohm.

p/n: EAB60866701

Top View

Side View

LCD DV 42SL80

88 February 2010

INTERCONNECT DIAGRAM (11 X 17 Foldout) SECTION

This section shows the Interconnect Diagram called the 11X17

foldout that

foldout that’

’s available in the Paper and Adobe version of the

s available in the Paper and Adobe version of the

Training Manual.

Use the Adobe version to zoom in for easier reading.

When Printing the Interconnect diagram, print from the Adobe

version and print onto 11X17 size paper for best results.

42SL80 INTERCONNECT DIAGRAM

Power Supply

Front IR

IR Receiver

Intelligent Sensor

SMPS TEST 1: To Force Power Supply On.

Disconnect P800 on Main board.

Load the 5V line using a 12V light bulb.

Jump pins 7,8,9 or 10 (5V) to pin 2 using a 100

resistor. (Test Voltage Outputs 12V, 24V to Main

and 24V to both Inverters).

SMPS TEST 2: Jump pins 7,8,9 or 10 (5V) to pin 20

(INV-ON). The Backlights should turn on.

LVDS

*PWM-DIM (P-DIM) is open on the Main board, n/c.

*A-DIM is fixed and does not move.

12V to T-CON

Pin 48~51.

Intelligent Sensor

TO TFT MODULE

UC1

FL3

1) Gnd

2) 1.8V

3) 3.3V

TO TFT MODULE

T-CON BOARD

(TFT Driver)

Gnd Protect

U11

U12

U10

(VGL) Pin 2

(VGH_M) Pin 4

(VDD_LCM) Pin 56,57,58

(VCC) Pin 53,54 26V

16V -5V

3.3V

26V

16V-5V 3.3V

2.78V

U13

FL2 Gnd

Protect

D10

3.3V

C 3.3V

20.5V

14.25V

-2.4V

R704

R705

R706

3.3V

26V

27V

C744

R721

Gnd

-5V

VCC

(CN1) Pin 48-51 F1 (12V)

125V / 3A

CN1 CN2

U5 B+ 12V

16V

VGH_M

16V

VGL

12V

3.3V

CN4

CN3

C308

C307

C306

C305

16.3V 3.3V

C304

C303

C302

C301

16.3V3.3V

CN5

(VDD_LCM) Pin 3,4,5

(VCC) Pin 7,8

(VGL) Pin 59

(VGH_M) Pin 57

Gnd

3.8V P/P

9.97Mhz

VDD

1~4) Gnd

5) 0V

6) 3.3V

7) 3.3V

8) 3.3V

1) 6.9V

2) 13.7V

3) 15.7V

4) 13.7V

5) 13.0V

6) 12.0V

7) 10.9V

8) Gnd

9) 16.0V

10) 10.1V

11) 8.2V

12) 7.7V

13) 3.3V

14) 3.3V

15) 3.3V

16) Gnd

17) Gnd

18) Gnd

19) 5.8V

20) 5.0V

21) 3.9V

22) 2.9V

23) 6.0V

24) Gnd

25) 2.2V

26) 0.3V

27) 2.2V

28) 6.9V

U12

P204

IC251

IC252 MC201

P101 SK100

D221D222

T101T102 IC102 IC502

IC103

IC501

T501

3.15A/250V

L600

L601

BD101 Q606

D603

Q605

D602

39uF/450V C616

C615

C614

C613

C612

C611

Q502

Q503Q501

Q111 Q110

P201P205

Q101

F100

6.3A/250V

CX102

CX101

CX105

CX103

CX104

L102

L103

L101

R103

RL101

39uF/450V

(1)

(19) Analog Video

(4) Tuner 5V_TU

(8) Data

(9) Clock

(12) Dig DIF+

(13) Dig DIF-

(16) SIF

DDR

P800

IC801

Tru-

Motion

P801

IC801 Operates at

high temperature

X800

25Mhz

Q408

IC300

Q1000

IC604

IC901

IC900

IC1

X600

12Mhz Micro/Video

Processor

Mstar

IC404

IC504

SW600

IC1200

L304

P1000

Q500

TU500 Tuner

TDVW-H103F

X500

25Mhz

P803

N/A

IC502

12V LVDS

Pins 1~4

P300

MAIN BOARD

P100

L305

IC301

P400

IC2

IC500

D500

IC406

NAND

FLASH

IC400

IC605

IC602

D1003

R-

R+

L-

L+

Q406

IC600

Mstar

DDR

Audio

PC RS232

HDMI 1

HDMI 2

HDMI 3

HDMI

USB

Pr Pb

YPrPb Audio

Video LR

L406

L412

L422

L424

IC100

IC501

IC503

IC102

IC405

IC1000

IC601

Q600

IC800

IC606

IC401

IC402

Q407

Q405

Q605

Q400 E

Q604

BQ401

IC603

Q603

Q602

D600

Q300

D200

Q200

D129

IC101

Q101

Grayed Out Components are on the Back Side

Q501

P100

Front “Soft Switch” Keys

P101

Backlights

1.2K

Backlights

1.2K

Side A/V

P101

P201 "SMPS" to P400 "Main"

Pin Label STBY Run Diode Check

2PWR-ON0V4.9V 1.6V

3-6

7-10 5.2V 5.14V

11-12

13-14

Gnd Gnd Gnd Gnd

15 Gnd Gnd Gnd Gnd

17-18

21 *A-DIM 0V 1.6V

N/C N/C N/C Open

Gnd Gnd GndGnd

5.14V Open

12V 0V 11.9V 0.27V

24V 0V 24.7V 0.42V

Open

ERR OUT 0V 0V Open

*P-DIM

16 A-Gnd Gnd Gnd Gnd

20 I-C 0V 4.3V Open

23 N/C N/C N/C Open

24 N/C N/C Open

Stand-by 5V

Pin Label STBY Run Diode

Check

11 DUTY_M1 0V 0.71V-2.4V OPEN

10 GND GND GND GND

9 DUTY_M2 0V 0.71V-2.4V OPEN

8 FB_S1 0V 0.96V 2.9V

7 ON/OFF 0V 4.3V OPEN

6 STB 0V 3.2V OPEN

5 VREF 0V 1.0V OPEN

4 FB_M1 0V 1.0V 2.9V

3 SRT 0V 1.4V OPEN

2 SS 0V 2.9V OPEN

1CT_SYNC_IN0V 1.5V 1.7V

CN3 "Inverter A" To CN203 "Inverter B"

Diode

Check

OPEN

GND

OPEN

2.9V

OPEN

2.9V

OPEN

1.7V

"A" "B"

P201

100

PWR ON

317511 915 1319 1721

428 612 1016 1420 1822

STBY 5V

24V 12V

Gnd

STBY 5V

24V 12V

12V Light Bulb

SMPS TEST 1

P201

100

317511 915 1319 1721

428 612 1016 1420 1822

STBY 5V

24V 12V

Gnd

STBY 5V

12V Light Bulb

24V 12V

100

INV-ON

SMPS TEST 2

P1000 “Main” to P100 “Front IR”

Pin Label STBY Run

1 SCL 0V 3.2V 1.6V

2 SDA 0V 3.2V 1.6V

3 Gnd Gnd Gnd Gnd

4 Key1 3.26V 3.26V 1.0V

5 Key2 3.26V 3.26V 1.3V

6 5V_ST 5.1V 5.1V 1.1V

7 Gnd Gnd Gnd Gnd

8 Warm_ST Gnd Gnd Gnd

Diode Check

Remote Diode Check

9IR4.18V Open

10 Gnd Gnd Gnd

11 3.3V_ST 3.31V 0.67V

12 PWR_ON 0V Open

Pin Label STBY Run

4.18V

Gnd

3.31V

3.29V

P1000 “Main” to P100 “Front IR”

STBY 170V

RUN 188.5V

Inverter A

T101

35V

680

35V

680

65V/ 12A

Q104 Q102 Q2 Q4

CN5

Q103 Q3 Q6

CN1

CN3

CN2

Q106

U101 & U1 are DC-AC Inverter

Control ICs

U101

C43

Do Not

Adjust

Inverter B

CN201

CN203

T201 T301

35V

680uF

65V/ 12A

Q302Q304Q204Q202

CN205

Q306

Q206

Q203 Q303

U201 & U301 are DC-AC

Inverter Control ICs

U201 U301

C208C243

35V

680uF

+-+

24V

See second page of Interconnect

Diagram for Main board DC Voltages

See pages 3/4 of Interconnect

Diagram for LVDS Waveforms

1616

Pin 1 T201/T301

29.2V p/p 48kHz

Pin 6 T201/T301

30V p/p 48kHz

Pin 1 T101/T1

29.2V p/p 48kHz

Pin 6 T101/T1

30V p/p 48kHz

CN2 "Inverter A" to CN3 "T-CON"

Diode Check

Run STBYLabel

Gnd

Scan 2

Gnd Gnd Gnd

Open

Scan 1

n/c

Open

0.67V-2.4V

Openn/c n/c

Diode Check

Gnd

0.98V

T-CON Side

A2 A1

(19)

Indicates Hot

Ground

P100 “Main” to P101 “Side A/V”

Pin Label STBY Run

8 Gnd Gnd Gnd

CVBS_IN 0V

6Gnd

Open

AV_DET

Gnd

AV_L_IN Open

3Gnd

AV_R_IN Open

1Gnd

Diode Check

Gnd

Gnd Gnd

Gnd

0.07V

P101 “Side A/V” to P100 “Main”

Pin Label STBY Run

1Diode Check

Gnd Gnd Gnd

CVBS_IN 0V Open

Gnd

Open

AV_DET

Gnd

AV_L_IN Open

Gnd Gnd

AV_R_IN Open

Gnd

Gnd Gnd

Gnd

MC1

Black

To Top 6 and Bottom 6 bulbs

To Center 13 bulbs

SC1

Black

PANEL BACKLIGHT CONNECTIONS

To Top 6 and Bottom 6 bulbs

To Center 13 bulbs

PANEL BACKLIGHT CONNECTIONS

P204 "SMPS" to CN1 "Inverter A"

Pin Label STBY Run Diode Check

1,2,3,4,5 24V 0V 24.7V 0.42V

6,7,8,9,10 Gnd Gnd Gnd Gnd

11 A-DIM 1.7V Open

12 *I-C 4.3V

13 *PWM-DIM N/C

14 ERROR 0V

Open

*I-C is Inverter On

*P-DIM is not used on this pin.

P205 "SMPS" to CN501 "Inverter B"

Diode CheckRun STBYLabel

1,2,3,4,5

6,7,8,9,10

24V

Gnd

A-DIM

*I-C

0V 24.7V 0.42V

Gnd Gnd Gnd

1.7V Open

4.3V

0V Open

Spks

42SL80 MAIN (FRONT SIDE) SIMICONDUCTORS

IC300 +1.8V AMP IC404 +1.8V_MEMC IC504 +3.3V_PVSB IC605 Reset Gen Q500 Tuner Video IC403 +1.6V_MEMC

Pin Regulator Pin Regulator Pin Regulator Pin for Power_Det Pin Buffer Pin Regulator

[1] Gnd [1] 0.8V [1] 4.94V [1] Gnd B 1.7V [1] 0V

[2] 1.8V [2] Gnd [2] 4.94V [2] 3.5V C 0V [2] 0.8V

[3] 3.3V [3] 4.92V [3] Gnd [3] 3.3V E 2.3V [3] 1.2V

[4] 6.5V [4] 3.4V [4] 1.2V

IC400 +1.8V_DDR [5] 4.8V [5] 1.25V Q406 5V Switch Q1000 Moving LED [5] 1.8V

Pin Regulator [6] 1.8V Pin Control Pin Inverter [6] 5.0V

[1] n/c [7] 1.8V IC602 HDCP B 0.6V B 0V [7] 1.2V

[2] 3.2V [8] 4.8V Pin EEPROM C 0V C 3.3V [8] 5.0V

[3] 3.2V [1] Gnd E Gnd E Gnd

[4] n/c IC406 +3.3V_ST [2] Gnd

[5] n/c Pin Regulator [3] 5.0V Q408 +5V/12VLVDS D500 Speed Up Reset

[6] 1.8V [1] 0V [4] Gnd Pin Switch Pin IC502

[7] 0.8V [2] 3.3V [5] 3.3V [1] 5.1V C 3.4V

[8] Gnd [3] 5.0V [6] 3.3V [2] 0.29V A 3.38V

[7] 5.0V [3] 11.9V

IC500 9V Reg [8] 5.0V [4] 5.99V D1003 Moving LED

Pin to IC501 Tuner 5V [5] 11.98V Pin Routing

[1] 12V [6] 11.98V A1 0V

[2] Gnd [7] 5.06V C 0.1V

[3] 8.9V [8] 5.06V A2 0V

42SL80 MAIN (BACK SIDE) SIMICONDUCTOR

IC100 RS232 IC102 RGB IC405 +5V EXT IC503 +1.2V_PVSB IC606 Micro IC600 IC603 Reset Gen Q401 INV_ON Q603 Power_On_

Pin Rx/Tx Pin EEPROM Pin Regulator Pin Regulator Pin EEPROM Pin for IC600 Pin Inverter Pin Delay Switch

[1] 3.3V [1] Gnd [1] 0.8V [1] 0V [1] Gnd [1] 0V B 0.05V B 0V

[2] 5.56V [2] Gnd [2] Gnd [2] 3.3V [2] Gnd [2] 0V C 4.35V C 0.04V

[3] 0.02V [3] Gnd [3] 12V [3] 3.4V [3] Gnd [3] 3.3V E Gnd E Gnd

[4] 0.03V [4] Gnd [4] 9.6V [4] 0V [4] Gnd

[5] 5.5V [5] 3.3V [5] 5V [5] 0V [5] 3.24V Q101 IR RS232 Q405 12V LVDS Q604 Power_Det

[6] 5.5V [6] 3.3V [6] 4.97V [6] 1.2V [6] 3.24V Pin Buffer Pin Switch Control Pin Switch

[7] 5.5V [7] 3.18V [7] 4.97V [7] 0.8V [7] 0V B 0.634V B 0.05V B 0V

[8] 0V [8] 0V [8] 1.9V [8] 0V [8] 3.24V C 0V C 0.65V C 3.3V

[9] 3.29V E 0V E Gnd E Gnd

[10] 3.24V IC401 +1.26V_VDDC IC504 +1.26V_PVSB IC800 SPI Flash IC801

[11] n/c Pin Regulator Pin Regulator Pin Memory Q200 HDMI CEC Q407 12V LVDS Q605 Power_Det

[12] 3.31V [1] 8.0V Oscilloscope ONL

[1] 0.8V [1] 0V Pin Pin Source Pin +12V Side

[13] 0V [2] Gnd [2] 0V [2] 0.8V [1] 3.2V B 0.65V B 0.65V

[14] 5.5V [3] 5.0V IC501 +5V_TU [3] 11.8V [3] 3.2V [2] 3.2V C 0.0V C 0.0V

[15] Gnd [4] 6.0V Pin for Tuner [4] 9.6V [4] 0V [3] 0V E Gnd E Gnd

[16] 3.29V [5] 4.9V [1] 8.92V [5] 5.0V [5] 0V [4] 0V

[6] 0V [2] 1.88V [6] 5.0V [6] 0.09V [5] 0V Q501 Tuner SIF D129 5V Routing

IC101 SPIF Optical [7] 0V [3] 5.04V [7] 5.0V [7] 3.2V [6] 3.16V Pin Buffer Pin for IC1200

Pin Audio [8] 3.2V [4] 0V [8] 0.9V [8] 3.2V B 2.4V A1 0.03V

[1] 0.03V [5] Gnd Q300 Audio Mute C 0V C 4.5V

[2] 0V IC402 +3.3V_MEMC IC601 Serial Flash IC1000 USB +5V Pin Switch E 3.0V A2 5.1V

[3] 0V Pin Regulator Pin for Boot Pin Switch B 0.62V

[4] 0V [1] 8.0V Oscilloscope ONL

[1] 0.04V [1] 4.95V C 0.01V Q600 Write Protect D200 Shunt for

[5] 0V [2] Gnd [2] 3.2V [2] Gnd E Gnd Pin for IC601 Pin Q200

[3] 4.98V [3] 2.5V [3] 3.21V B 0V A1 0V

[4] 7.6V [4] 0V [4] 4.95V Q400 PWR On/Off C 2.5V C 3.1V

[5] 4.9V [5] 0V [5] 0V Pin Switch E Gnd A2 3.2V

[6] 3.3V [6] 0V [6] 4.95V B 2.9V

[7] 3.3V [7] 3.2V C 5V Q602 S5/S6 Reset D600 Audio Mute

[8] 0V [8] 3.2V E 5V Pin Switch for Mstar Pin Routing

B 0V A1 0.01V

C 3.28V C 2.7V

E 0V A2 3.29V

WARNING

Measure Pin

1 with O-

scope ONLY

WARNING

Measure Pin

1 with O-

scope ONLY

42SL80 LVDS P800 WAVEFORMS

42SL80 P800 LVDS CABLE WAVEFORMS:

Waveforms taken using SMTP Color Bar input.

All readings give the Scale 10mV and Time Base

related to scope settings.

Top waveform in each image gives a slower rate,

2us per division. Outlined area is shown in the

bottom waveform at 500ns per division time

base.

Pin 11 Pin 12 Pin 16

Pin 24

Pin 35

Pin 38Pin 37

Pin 30

Pin 23

Pin 20

Pin 13 Pin 14

Pin 17 Pin 21

Pin 27 Pin 28

Pin 36

Pin 32

Pin 39 Pin 40

Pin 19 Pin 22

Pin 29

Pin 33

42SL80 LVDS P801 WAVEFORMS

42SL80 P801 LVDS CABLE WAVEFORMS:

Waveforms taken using SMTP Color Bar input.

All readings give the Scale 10mV and Time Base

related to scope settings.

Top waveform in each image gives a slower rate,

2us per division. Outlined area is shown in the

bottom waveform at 500ns per division time

base.

Pin 3

Pin 12

Pin 15

Pin 22

Pin 29 Pin 30

Pin 27

Pin 16

Pin 8

Pin 4 Pin 5 Pin 6

Pin 11

Pin 9 Pin 13 Pin 14

Pin 19 Pin 20 Pin 21

Pin 28

Pin 24 Pin 25

Pin 31 Pin 32

42SL80

Direct View LCD

This concludes the 42SL80

training session.

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