Telit Communications S p A GE865 Quadband GSM/ GPRS Module User Manual 1vv0300799 GE865 Hardware User Guide r6
Telit Communications S.p.A. Quadband GSM/ GPRS Module 1vv0300799 GE865 Hardware User Guide r6
User Manual
GE865 Hardware User Guide
1vv0300799 Rev.6 - 04.06.09
GE865 Hardware User Guide
1vv0300799 Rev.6 - 04/06/09
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 2 of 58
Contents
1
Overview ........................................................................................................................... 5
2
GE865 Mechanical Dimensions....................................................................................... 6
3
GE865 module connections ............................................................................................ 7
3.1 PIN-OUT ................................................................................................................................ 7
3.1.1
BGA Balls Layout ........................................................................................................................... 10
4
Hardware Commands .................................................................................................... 11
4.1 Turning ON the GE865 ....................................................................................................... 11
4.2 Turning OFF the GE865 ..................................................................................................... 14
4.2.1
Hardware shutdown ....................................................................................................................... 14
4.2.2
Hardware Unconditional Restart .................................................................................................... 15
5
Power Supply.................................................................................................................. 17
5.1 Power Supply Requirements ............................................................................................ 17
5.2 Power Consumption .......................................................................................................... 18
5.3 General Design Rules ........................................................................................................ 19
5.3.1
Electrical Design Guidelines .......................................................................................................... 19
5.3.1.1
+ 5V input Source Power Supply Design Guidelines ................................................................ 19
5.3.1.2
+ 12V input Source Power Supply Design Guidelines .............................................................. 20
5.3.1.3
Battery Source Power Supply Design Guidelines ..................................................................... 22
5.3.2
Thermal Design Guidelines ........................................................................................................... 23
5.3.3
Power Supply PCB layout Guidelines ........................................................................................... 24
6
Antenna ........................................................................................................................... 25
6.1 GSM Antenna Requirements ............................................................................................. 25
6.2 GSM Antenna - PCB line Guidelines................................................................................. 26
6.3 GSM Antenna - Installation Guidelines ............................................................................ 27
7
Logic level specifications .............................................................................................. 28
7.1 Reset signal ....................................................................................................................... 29
8
Serial Ports ..................................................................................................................... 30
8.1 MODEM SERIAL PORT ...................................................................................................... 30
8.2 RS232 level translation ...................................................................................................... 32
8.3 5V UART level translation ................................................................................................. 35
9
Audio Section Overview ................................................................................................ 37
9.1 Microphone Paths Characteristic and Requirements ..................................................... 37
10
OUTPUT LINES (Speaker) .............................................................................................. 38
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10.1 Short description ............................................................................................................... 38
10.2 Output Lines Characteristics ............................................................................................ 38
11
General Purpose I/O ....................................................................................................... 39
11.1 GPIO Logic levels .............................................................................................................. 40
11.2 Using a GPIO Pad as INPUT .............................................................................................. 41
11.3 Using a GPIO Pad as OUTPUT .......................................................................................... 41
11.4 Using the RF Transmission Control GPIO4 ..................................................................... 41
11.5 Using the RFTXMON Output GPIO5 ................................................................................. 41
11.6 Using the Alarm Output GPIO6 ......................................................................................... 42
11.7 Using the Buzzer Output GPIO7 ....................................................................................... 42
11.8 Indication of network service availability ......................................................................... 43
11.9 RTC Bypass out ................................................................................................................. 44
11.10 External SIM Holder Implementation ............................................................................ 44
12
DAC and ADC section .................................................................................................... 45
12.1 DAC Converter ................................................................................................................... 45
12.1.1
Description ..................................................................................................................................... 45
12.1.2
Enabling DAC ................................................................................................................................ 46
12.1.3
Low Pass Filter Example ............................................................................................................... 46
12.2 ADC Converter ................................................................................................................... 47
12.2.1
Description ..................................................................................................................................... 47
12.2.2
Using ADC Converter .................................................................................................................... 47
12.3 Mounting the GE865 on your Board ................................................................................. 48
12.3.1
General .......................................................................................................................................... 48
12.3.2
Module finishing & dimensions ...................................................................................................... 48
12.3.3
Suggested Inhibit Area .................................................................................................................. 49
12.3.4
Debug of the GE865 in production ................................................................................................ 50
12.3.5
Stencil ............................................................................................................................................ 50
12.3.6
PCB pad design ............................................................................................................................. 51
12.3.7
Solder paste ................................................................................................................................... 52
12.3.8
GE865 Solder reflow ...................................................................................................................... 53
12.4 Packing system .................................................................................................................. 54
12.4.1
Moisture sensibility ........................................................................................................................ 55
13
Conformity Assessment Issues .................................................................................... 56
14
SAFETY RECOMMANDATIONS ..................................................................................... 57
15
Document Change Log .................................................................................................. 58
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DISCLAIMER
The information contained in this document is the proprietary information of Telit Communications
S.p.A. and its affiliates (“TELIT”). The contents are confidential and any disclosure to persons other
than the officers, employees, agents or subcontractors of the owner or licensee of this document,
without the prior written consent of Telit, is strictly prohibited.
Telit makes every effort to ensure the quality of the information it makes available. Notwithstanding the
foregoing, Telit does not make any warranty as to the information contained herein, and does not
accept any liability for any injury, loss or damage of any kind incurred by use of or reliance upon the
information.
Telit disclaims any and all responsibility for the application of the devices characterized in this
document, and notes that the application of the device must comply with the safety standards of the
applicable country, and where applicable, with the relevant wiring rules.
Telit reserves the right to make modifications, additions and deletions to this document due to
typographical errors, inaccurate information, or improvements to programs and/or equipment at any
time and without notice. Such changes will, nevertheless be incorporated into new editions of this
application note.
All rights reserved.
© 2009 Telit Communications S.p.A.
GE865 Hardware User Guide
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1 Overview
The aim of this document is the description of some hardware solutions useful for developing a product with the
Telit GE865-QUAD module.
In this document all the basic functions of a mobile phone will be taken into account; for each one of them a
proper hardware solution will be suggested and eventually the wrong solutions and common errors to be
avoided will be evidenced. Obviously this document cannot embrace the whole hardware solutions and products
that may be designed. The wrong solutions to be avoided shall be considered as mandatory, while the
suggested hardware configurations shall not be considered mandatory, instead the information given shall be
used as a guide and a starting point for properly developing your product with the Telit GE865-QUAD module. For
further hardware details that may not be explained in this document refer to the Telit GE865 Product Description
document where all the hardware information is reported.
NOTICE
(EN) The integration of the GSM/GPRS
GE865-QUAD
cellular module within user application shall be done
according to the design rules described in this manual.
(IT) L’integrazione del modulo cellulare GSM/GPRS
GE865-QUAD
all’interno dell’applicazione dell’utente
dovrà rispettare le indicazioni progettuali descritte in questo manuale.
(DE) Die integration des
GE865-QUAD
GSM/GPRS Mobilfunk-Moduls in ein Gerät muß gemäß der in
diesem Dokument beschriebenen Kunstruktionsregeln erfolgen
(SL) Integracija GSM/GPRS
GE865-QUAD
modula v uporabniški aplikaciji bo morala upoštevati projektna
navodila, opisana v tem piročniku.
(SP) La utilización del modulo GSM/GPRS
GE865-QUAD
debe ser conforme a los usos para los cuales ha
sido deseñado descritos en este manual del usuario.
(FR) L’intégration du module cellulaire GSM/GPRS
GE865-QUAD
dans l’application de l’utilisateur sera
faite selon les règles de conception décrites dans ce manuel.
The information presented in this document is believed to be accurate and reliable. However, no responsibility is
assumed by Telit Communications S.p.A. for its use, nor any infringement of patents or other rights of third
parties which may result from its use. No license is granted by implication or otherwise under any patent rights of
Telit Communications S.p.A. other than for circuitry embodied in Telit products. This document is subject to
change without notice.
GE865
-
QUAD
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2 GE865 Mechanical Dimensions
The Telit GE865-QUAD module overall dimension are:
• Length: 22 mm
• Width: 22 mm
• Thickness: 3.0 mm
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3 GE865 module connections
3.1 PIN-OUT
Ball Signal I/O Function Note Type
Audio
E8 EAR- AO Earphone signal output, phase - Audio
D8 EAR+ AO Earphone signal output, phase + Audio
B8 MIC+ AI Mic.signal input; phase+ Audio
C8 MIC- AI Mic.signal input; phase- Audio
SIM card interface
A5 SIMCLK O External SIM signal – Clock 1,8 / 3V
A8 SIMRST O External SIM signal – Reset 1,8 / 3V
A6 SIMIO I/O External SIM signal – Data I/O 4.7K Pull up 1,8 / 3V
B7 SIMIN I External SIM signal – Presence (active low) 1,8 / 3V
A7 SIMVCC - External SIM signal – Power supply for the SIM 1,8 / 3V
Trace
D1 TXD_AUX O Auxiliary UART (TX Data) CMOS 2.8V
E1 RXD_AUX I Auxiliary UART (RX Data) CMOS 2.8V
Prog. / Data + HW Flow Control
A3 C103/TXD I Serial data input (TXD) from DTE CMOS 2.8V
A4 C104/RXD O Serial data output to DTE CMOS 2.8V
B3 C108/DTR I Input for Data terminal ready signal (DTR) from
DTE CMOS 2.8V
A1 C105/RTS I Input for Request to send signal (RTS) from
DTE CMOS 2.8V
A2 C106/CTS O Output for Clear to send signal (CTS) to DTE CMOS 2.8V
B5 C109/DCD O Output for Data carrier detect signal (DCD) to
DTE CMOS 2.8V
B2 C107/DSR O Output for Data set ready signal (DSR) to DTE CMOS 2.8V
B4 C125/RING O Output for Ring indicator signal (RI) to DTE CMOS 2.8V
DAC and ADC
G7 DAC_OUT AO Digital/Analog converter output D/A
F5 ADC_IN1 AI Analog/Digital converter input A/D
F6 ADC_IN2 AI Analog/Digital converter input A/D
Miscellaneous Functions
C1 RESET* I Reset input
H2 VRTC AO VRTC Backup capacitor Power
G8 STAT_LED O Status indicator led CMOS 1.8V
B1 ON_OFF* I Input command for switching power ON or OFF
(toggle command). 47K Pull Up Pull up to VRTC
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Ball Signal I/O Function Note Type
E2 PWRMON O Power ON Monitor CMOS 2.8V
H5 Antenna O Antenna output – 50 ohm RF
H1 Service I
Service pin shall be used to upgrade the
module from ASC1 (RXD AUX, TXD_AUX).
The pin shall be tied low to enable the feature
only in case of a Reflashing activity. It is
required, for debug purpose, to be connected
to a test pad on the final application.
CMOS 2.8V
GPIO
D3 GPIO_01 I/O GPIO01 Configurable GPIO CMOS 2.8V
D2 GPIO_02 / JDR I/O GPIO02 I/O pin / Jammer Detect Report CMOS 2.8V
E4 GPIO_03 I/O GPIO03 GPIO I/O pin CMOS 2.8V
H7 GPIO_04 / TX_DISAB I/O GPIO04 Configurable GPIO / TX Disable input CMOS 2.8V
G2 GPIO_05 / RFTXMON I/O GPIO05 Configurable GPIO / Transmitter ON
monitor CMOS 2.8V
H8 GPIO_06 / ALARM I/O GPIO06 Configurable GPIO / ALARM CMOS 2.8V
G6 GPIO_07 / BUZZER I/O GPIO07 Configurable GPIO / Buzzer CMOS 2.8V
D4 GPIO_08 I/O GPIO08 Configurable GPIO CMOS 2.8V
F4 GPIO_09 I/O GPIO09 4.7 K Pull Up Open Drain
E3 GPIO_10 I/O GPIO10 4.7 K Pull Up Open Drain
Power Supply
F1 VBATT - Main power supply (Baseband) Power
F2 VBATT_PA - Main power supply (Radio PA) Power
F3 VBATT_PA - Main power supply (Radio PA) Power
G1 GND - Ground Power
C2 GND - Ground Power
C7 GND - Ground Power
E5 GND - Ground Power
E7 GND - Ground Power
G5 GND - Ground Power
G4 GND - Ground Power
G3 GND - Ground Power
H3 GND - Ground Power
H6 GND - Ground Power
RESERVED
B6 -
C3 -
C4 -
C5 -
C6 -
D5 -
D6 -
D7 -
E6 -
F7 -
F8 -
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NOTE: RESERVED pins must not be connected
NOTE: If not used, almost all pins should be left disconnected. The only exceptions are the following
pins:
pin
signal
F1,F2,F3
VBATT &
VBATT_PA
G1, C2, C7, E5, E7, G5, G4,
G3, H3, H6 GND
B1
ON/OFF*
A3
TXD
C1
RESET*
A4
RXD
A1
RTS
1
D1
TXD_AUX
E1
RXD_AUX
H1
Service
1
RTS should be connected to the GND ( on the module side) if flow control is not used
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3.1.1 BGA Balls Layout
TOP VIEW
A B C D E F G H
1
C105 /
RTS ON_OFF RESET* TXD_AUX RXD_AUX VBATT GND SERVICE
2
C106/CTS C107/DSR GND GPIO_02 PWRMON VBATT_P
A GPIO_05 VRTC
3
C103_TXD C108/DTR - GPIO_01 GPIO_10 VBATT_P
A GND GND
4
C104/RXD C125/RING - GPIO_08 GPIO_03 GPIO_09 GND
5
SIMCLK C109/DCD - - GND ADC1 GND ANT
6
SIMIO - - - - ADC2 GPIO_07 GND
7
SIMVCC SIMIN GND - GND - DAC GPIO_04
8
SIMRST MIC+ MIC- EAR+ EAR- - STATLED GPIO_06
LEGENDA:
NOTE: The pin defined as H4 has to be considered RESERVED and not connected on any pin in the
application. The related area on the application has to be kept empty.
AUDIO
SIM CAR
D
ANTENNA
UART
S
DAC and ADC
MISCELLANEOUS
GPIO
POWER SUPPLY VBATT
POWER SUPPLY GND
RESERVED
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4 Hardware Commands
4.1 Turning ON the GE865
To turn on the GE865 the pad ON# must be tied low for at least 1 seconds and then released.
The maximum current that can be drained from the ON# pad is 0,1 mA.
A simple circuit to do it is:
NOTE: don't use any pull up resistor on the ON# line, it is internally pulled up. Using pull up resistor may bring to
latch up problems on the GE865 power regulator and improper power on/off of the module. The line ON# must be
connected only in open collector configuration.
NOTE: In this document all the lines that are inverted, hence have active low signals are labeled with a name that
ends with”#" or with a bar over the name.
TIP: To check if the device has powered on, the hardware line PWRMON should be monitored. After 900ms the line
raised up the device could be considered powered on.
ON#
Power ON impulse
GND
R1
R2
Q1
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A flow chart showing the proper turn on procedure is displayed below:
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For example:
1- Let's assume you need to drive the ON# pad with a totem pole output of a +3/5 V microcontroller
(uP_OUT1):
2- Let's assume you need to drive the ON# pad directly with an ON/OFF button:
1s
10k
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4.2 Turning OFF the GE865
The turning off of the device can be done in three ways:
• by software command (see GE865 Software User Guide)
• by hardware shutdown
• by Hardware Unconditional Restart
When the device is shut down by software command or by hardware shutdown, it issues to the
network a detach request that informs the network that the device will not be reachable any more.
4.2.1 Hardware shutdown
To turn OFF the GE865 the pad ON# must be tied low for at least 2 seconds and then released.
The same circuitry and timing for the power on shall be used.
The device shuts down after the release of the ON# pad.
TIP: To check if the device has powered off, the hardware line PWRMON should be monitored. When PWRMON goes
low, the device has powered off.
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4.2.2 Hardware Unconditional Restart
To unconditionally Restart the GE865, the pad RESET# must be tied low for at least 200 milliseconds
and then released.
A simple circuit to do it is:
The following flow chart shows the proper Reset procedure:
NOTE: don't use any pull up resistor on the RESET# line nor any totem pole digital output. Using pull up resistor
may bring to latch up problems on the GE865 power regulator and improper functioning of the module. The line
RESET# must be connected only in open collector configuration.
RESET#
Unconditional Restart
impulse
GND
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NOTE: The unconditional hardware Restart should be always implemented on the boards and software should use it
as an emergency exit procedure.
For example:
1- Let's assume you need to drive the RESET# pad with a totem pole output of a +3/5 V
microcontroller (uP_OUT2):
NOTE: The RESET# signal is internally pulled up so the pin can be left floating if not used
10k
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5 Power Supply
The power supply circuitry and board layout are a very important part in the full product design and
they strongly reflect on the product overall performances, hence read carefully the requirements and
the guidelines that will follow for a proper design.
5.1 Power Supply Requirements
The external power supply must be connected to VBATT & VBATT_PA signals and must fulfill the
following requirements:
POWER SUPPLY
Nominal Supply Voltage
3.8 V
Normal Operating Voltage Range
3.4 V - 4.2 V
Extended Operating Voltage Range
3.22 V - 4.5 V
NOTE: The Operating Voltage Range MUST never be exceeded; care must be taken in order to fulfill
min/max voltage requirement
NOTE: Overshoot voltage (regarding MAX Extended Operating Voltage) and drop in voltage (regarding
MIN Extended Operating Voltage) MUST never be exceeded;
The “Extended Operating Voltage Range” can be used only with completely assumption and application
of the HW User guide suggestions.
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5.2 Power Consumption
The GE865-QUAD power consumptions are: (Preliminary Values)
GE865
-
QUAD
Mode
Average (
mA)
Mode description
IDLE mode
Stand by mode; no call in progress
AT+CFUN=1 23,9 Normal mode: full functionality of the module
AT+CFUN=4 22 Disabled TX and RX; module is not registered on the
network
AT+CFUN=0 or
AT+CFUN=5 2,4
Power saving: CFUN=0 module registered on the network
and can receive voice call or an SMS; but it is not possible
to send AT commands; module wakes up with an
unsolicited code (call or SMS) or rising RTS line. CFUN=5
full functionality with power saving; module registered on
the network can receive incoming calls and SMS
RX mode
GSM Receiving data mode
1 slot in downlink 52,3
2 slot in downlink 65,2
3 slot in downlink 78,6
4 slot in downlink 88,4
GSM TX and RX mode
GSM Sending data mode Min power level 78,1
Max power level 200,1
GPRS (class 10) TX and RX mode
GPRS Sending data mode Min power level 123,7
Max power level 370,8
POWER OFF
Module Powered Off
Power Off <26uA
The GSM system is made in a way that the RF transmission is not continuous, else it is packed into
bursts at a base frequency of about 216 Hz, and the relative current peaks can be as high as about
2A. Therefore the power supply has to be designed in order to withstand with these current peaks
without big voltage drops; this means that both the electrical design and the board layout must be
designed for this current flow.
If the layout of the PCB is not well designed a strong noise floor is generated on the ground and the
supply; this will reflect on all the audio paths producing an audible annoying noise at 216 Hz; if the
voltage drop during the peak current absorption is too much, then the device may even shutdown as a
consequence of the supply voltage drop.
TIP: The electrical design for the Power supply should be made ensuring it will be capable of a peak current output
of at least 2 A.
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5.3 General Design Rules
The principal guidelines for the Power Supply Design embrace three different design steps:
• the electrical design
• the thermal design
• the PCB layout.
5.3.1 Electrical Design Guidelines
The electrical design of the power supply depends strongly from the power source where this power is
drained. We will distinguish them into three categories:
• +5V input (typically PC internal regulator output)
• +12V input (typically automotive)
• Battery
5.3.1.1 + 5V input Source Power Supply Design Guidelines
• The desired output for the power supply is 3.8V, hence there's not a big difference between the
input source and the desired output and a linear regulator can be used. A switching power supply
will not be suited because of the low drop out requirements.
• When using a linear regulator, a proper heat sink shall be provided in order to dissipate the power
generated.
• A Bypass low ESR capacitor of adequate capacity must be provided in order to cut the current
absorption peaks close to the GE865, a 100µF tantalum capacitor is usually suited.
• Make sure the low ESR capacitor on the power supply output (usually a tantalum one) is rated at
least 10V.
• A protection diode should be inserted close to the power input, in order to save the GE865 from
power polarity inversion.
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An example of linear regulator with 5V input is:
5.3.1.2 + 12V input Source Power Supply Design Guidelines
• The desired output for the power supply is 3.8V, hence due to the big difference between the input
source and the desired output, a linear regulator is not suited and shall not be used. A switching
power supply will be preferable because of its better efficiency especially with the 2A peak current
load represented by the GE865.
• When using a switching regulator, a 500kHz or more switching frequency regulator is preferable
because of its smaller inductor size and its faster transient response. This allows the regulator to
respond quickly to the current peaks absorption.
• In any case the frequency and Switching design selection is related to the application to be
developed due to the fact the switching frequency could also generate EMC interferences.
• For car PB battery the input voltage can rise up to 15,8V and this should be kept in mind when
choosing components: all components in the power supply must withstand this voltage.
• A Bypass low ESR capacitor of adequate capacity must be provided in order to cut the current
absorption peaks, a 100µF tantalum capacitor is usually suited.
• Make sure the low ESR capacitor on the power supply output (usually a tantalum one) is rated at
least 10V.
• For Car applications a spike protection diode should be inserted close to the power input, in order
to clean the supply from spikes.
• A protection diode should be inserted close to the power input, in order to save the GE865-QUAD
from power polarity inversion. This can be the same diode as for spike protection.
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An example of switching regulator with 12V input is in the below schematic (it is split in 2 parts):
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5.3.1.3 Battery Source Power Supply Design Guidelines
• The desired nominal output for the power supply is 3.8V and the maximum voltage allowed is
4.2V, hence a single 3.7V Li-Ion cell battery type is suited for supplying the power to the Telit
GE865 module.
The three cells Ni/Cd or Ni/MH 3,6 V Nom. battery types or 4V PB types MUST NOT BE USED
DIRECTLY since their maximum voltage can rise over the absolute maximum voltage for the
GE865 and damage it.
NOTE: DON'T USE any Ni-Cd, Ni-MH, and Pb battery types directly connected with GE865. Their use can
lead to overvoltage on the GE865 and damage it. USE ONLY Li-Ion battery types.
• A Bypass low ESR capacitor of adequate capacity must be provided in order to cut the current
absorption peaks, a 100µF tantalum capacitor is usually suited.
• Make sure the low ESR capacitor (usually a tantalum one) is rated at least 10V.
• A protection diode should be inserted close to the power input, in order to save the GE865 from
power polarity inversion. Otherwise the battery connector should be done in a way to avoid polarity
inversions when connecting the battery.
• The battery capacity must be at least 500mAh in order to withstand the current peaks of 2A; the
suggested capacity is from 500mAh to 1000mAh.
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5.3.2 Thermal Design Guidelines
The thermal design for the power supply heat sink should be done with the following specifications:
• Average current consumption during transmission @PWR level max: 500mA
• Average current consumption during transmission @ PWR level min: 100mA
• Average current during Power Saving (CFUN=5): 2,4mA
• Average current during idle (Power Saving disabled) 24mA
NOTE: The average consumption during transmissions depends on the power level at which the device is requested
to transmit by the network. The average current consumption hence varies significantly.
Considering the very low current during idle, especially if Power Saving function is enabled, it is
possible to consider from the thermal point of view that the device absorbs current significantly only
during calls.
If we assume that the device stays into transmission for short periods of time (let's say few minutes)
and then remains for a quite long time in idle (let's say one hour), then the power supply has always
the time to cool down between the calls and the heat sink could be smaller than the calculated one for
500mA maximum RMS current, or even could be the simple chip package (no heat sink).
Moreover in the average network conditions the device is requested to transmit at a lower power level
than the maximum and hence the current consumption will be less than the 500mA, being usually
around 150mA.
For these reasons the thermal design is rarely a concern and the simple ground plane where the
power supply chip is placed can be enough to ensure a good thermal condition and avoid overheating.
For the heat generated by the GE865, you can consider it to be during transmission 1W max during
CSD/VOICE calls and 2W max during class10 GPRS upload.
This generated heat will be mostly conducted to the ground plane under the GE865; you must ensure
that your application can dissipate it.
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5.3.3 Power Supply PCB layout Guidelines
As seen on the electrical design guidelines the power supply shall have a low ESR capacitor on the
output to cut the current peaks and a protection diode on the input to protect the supply from spikes
and polarity inversion. The placement of these components is crucial for the correct working of the
circuitry. A misplaced component can be useless or can even decrease the power supply
performances.
• The Bypass low ESR capacitor must be placed close to the Telit GE865 power input pads or in the
case the power supply is a switching type it can be placed close to the inductor to cut the ripple
provided the PCB trace from the capacitor to the GE865 is wide enough to ensure a dropless
connection even during the 2A current peaks.
• The protection diode must be placed close to the input connector where the power source is
drained.
• The PCB traces from the input connector to the power regulator IC must be wide enough to ensure
no voltage drops occur when the 2A current peaks are absorbed. Note that this is not made in
order to save power loss but especially to avoid the voltage drops on the power line at the current
peaks frequency of 216 Hz that will reflect on all the components connected to that supply,
introducing the noise floor at the burst base frequency. For this reason while a voltage drop of 300-
400 mV may be acceptable from the power loss point of view, the same voltage drop may not be
acceptable from the noise point of view. If your application doesn't have audio interface but only
uses the data feature of the Telit GE865, then this noise is not so disturbing and power supply
layout design can be more forgiving.
• The PCB traces to the GE865 and the Bypass capacitor must be wide enough to ensure no
significant voltage drops occur when the 2A current peaks are absorbed. This is for the same
reason as previous point. Try to keep this trace as short as possible.
• The PCB traces connecting the Switching output to the inductor and the switching diode must be
kept as short as possible by placing the inductor and the diode very close to the power switching
IC (only for switching power supply). This is done in order to reduce the radiated field (noise) at the
switching frequency (100-500 kHz usually).
• The use of a good common ground plane is suggested.
• The placement of the power supply on the board should be done in such a way to guarantee that
the high current return paths in the ground plane are not overlapped to any noise sensitive circuitry
as the microphone amplifier/buffer or earphone amplifier.
• The power supply input cables should be kept separate from noise sensitive lines such as
microphone/earphone cables.
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6 Antenna
The antenna connection and board layout design are the most important part in the full product design
and they strongly reflect on the product overall performances, hence read carefully and follow the
requirements and the guidelines for a proper design.
6.1 GSM Antenna Requirements
As suggested on the Product Description the antenna and antenna line on PCB for a Telit GE865
device shall fulfill the following requirements:
ANTENNA REQUIREMENTS
Frequency range
Depending by frequency band(s) provided by
the network operator, the customer shall use
the most suitable antenna for that/those
band(s)
Bandwidth
70 MHz in GSM850, 80 MHz in GSM900,
170 MHz in DCS & 140 MHz PCS band
Gain
Gain < 3dBi
Impedance
50 ohm
Input power
> 2 W peak power
VSWR absolute
max <= 10:1
VSWR
recommended <= 2:1
When using the Telit GE865, since there's no antenna connector on the module, the antenna must be
connected to the GE865 through the PCB with the antenna pad (BGA Ball H5).
In the case that the antenna is not directly developed on the same PCB, hence directly connected at
the antenna pad of the GE865, then a PCB line is needed in order to connect with it or with its
connector.
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This line of transmission shall fulfill the following requirements:
ANTENNA LINE ON PCB REQUIREMENTS
Impedance
50 ohm
Max Attenuation
0,3 dB
N
o coupling with other signals allowed
Cold End (Ground Plane) of antenna shall be equipotential to
the GE865 ground pins
Furthermore if the device is developed for the US market and/or Canada market, it shall comply with
the FCC and/or IC approval requirements:
This device is to be used only for mobile and fixed application. In order to re-use the Telit FCC/IC
approvals the antenna(s) used for this transmitter must be installed to provide a separation distance of
at least 20 cm from all persons and must not be co-located or operating in conjunction with any other
antenna or transmitter. If antenna is installed with a separation distance of less than 20 cm from all
persons or is co-located or operating in conjunction with any other antenna or transmitter then
additional FCC/IC testing may be required. End-Users must be provided with transmitter operation
conditions for satisfying RF exposure compliance.
Antennas used for this OEM module must not exceed 3dBi gain for mobile and fixed operating
configurations.
6.2 GSM Antenna - PCB line Guidelines
• Ensure that the antenna line impedance is 50 ohm;
• Keep the antenna line on the PCB as short as possible, since the antenna line loss shall be less
than 0,3 dB;
• Antenna line must have uniform characteristics, constant cross section, avoid meanders and
abrupt curves;
• Keep, if possible, one layer of the PCB used only for the Ground plane;
• Surround (on the sides, over and under) the antenna line on PCB with Ground, avoid having other
signal tracks facing directly the antenna line track;
• The ground around the antenna line on PCB has to be strictly connected to the Ground Plane by
placing vias once per 2mm at least;
• Place EM noisy devices as far as possible from GE865 antenna line;
• Keep the antenna line far away from the GE865 power supply lines;
• If you have EM noisy devices around the PCB hosting the GE865, such as fast switching ICs, take
care of the shielding of the antenna line by burying it inside the layers of PCB and surround it with
Ground planes, or shield it with a metal frame cover.
• If you don't have EM noisy devices around the PCB of GE865, by using a strip-line on the
superficial copper layer for the antenna line, the line attenuation will be lower than a buried one;
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6.3 GSM Antenna - Installation Guidelines
• Install the antenna in a place covered by the GSM signal.
• If the device antenna is located greater then 20cm from the human body and there are no co-
located transmitter then the Telit FCC/IC approvals can be re-used by the end product
• If the device antenna is located less then 20cm from the human body or there are no co-located
transmitter then the additional FCC/IC testing may be required for the end product (Telit FCC/IC
approvals cannot be reused)
• Antenna shall not be installed inside metal cases
• Antenna shall be installed also according Antenna manufacturer instructions.
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7 Logic level specifications
Where not specifically stated, all the interface circuits work at 2.8V CMOS logic levels. The following
table shows the logic level specifications used in the Telit GE865 interface circuits:
Absolute Maximum Ratings -Not Functional
Parameter
Min
Max
Input level on any digital pin (CMOS 2.8)
when on -0.3V +3.1V
Input level on any digital pin (CMOS 1.8)
when on -0.3V +2.1V
Input voltage on analog pins when on -0.3V +3.0 V
Operating Range - Interface levels (2.8V CMOS)
Level
Min
Max
Input high level 2.1V 3.0V
Input low level 0V 0.5V
Output high level 2.2V 3.0V
Output low level 0V 0.35V
For 1.8V signals:
Operating Range - Interface levels (1.8V CMOS)
Level
Min
Max
Input high level 1.6V 2.0V
Input low level 0V 0.4V
Output high level 1,65V 2.0V
Output low level 0V 0.35V
Current characteristics
Level
Typical
Output Current 1mA
Input Current 1uA
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7.1 Reset signal
Signal
Function
I/O
Bga Ball
RESET# Phone reset I A2
RESET# is used to reset the GE865-QUAD modules. Whenever this signal is pulled low, the GE865 is
reset. When the device is reset it stops any operation. After the release of the reset GE865 is
unconditionally shut down, without doing any detach operation from the network where it is registered.
This behaviour is not a proper shut down because any GSM device is requested to issue a detach
request on turn off. For this reason the Reset signal must not be used to normally shutting down the
device, but only as an emergency exit in the rare case the device remains stuck waiting for some
network response.
The RESET# is internally controlled on start-up to achieve always a proper power-on reset sequence,
so there's no need to control this pin on start-up. It may only be used to reset a device already on that
is not responding to any command.
NOTE: do not use this signal to power off the GE865. Use the ON/OFF signal to perform this function or
the AT#SHDN command.
Reset Signal Operating levels:
Sign
al
Min
Max
RESET Input high 1.8V* 2.1V
RESET Input low 0V 0.2V
* this signal is internally pulled up so the pin can be left floating if not used.
If unused, this signal may be left unconnected. If used, then it must always be connected with an
open collector transistor, to permit to the internal circuitry the power on reset and under voltage
lockout functions.
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8 Serial Ports
The serial port on the Telit GE865-QUAD is the core of the interface between the module and OEM
hardware.
2 serial ports are available on the module:
• MODEM SERIAL PORT 1 (MAIN)
• MODEM SERIAL PORT 2 (AUX)
8.1 MODEM SERIAL PORT
Several configurations can be designed for the serial port on the OEM hardware, but the most
common are:
• RS232 PC com port
• microcontroller UART @ 2.8V - 3V (Universal Asynchronous Receive Transmit)
• microcontroller UART@ 5V or other voltages different from 2.8V
Depending from the type of serial port on the OEM hardware a level translator circuit may be needed
to make the system work. The only configuration that doesn't need a level translation is the 2.8V
UART.
The serial port on the GE865 is a +2.8V UART with all the 7 RS232 signals. It differs from the PC-
RS232 in the signal polarity (RS232 is reversed) and levels. The levels for the GE865 UART are the
CMOS levels:
Absolute Maximum Ratings -Not Functional
Parameter
Min
Max
Input level on any
digital pad when on -0.3V +3.1V
Input voltage on
analog pads when on
-0.3V +3.1V
Operating Range - Interface levels (2.8V CMOS)
Level
Min
Max
Input high level V
IH
2.1V 3.0 V
Input low level V
IL
0V 0.5V
Output high level V
OH
2.2V 3.0V
Output low level V
OL
0V 0.35V
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The signals of the GE865 serial port are:
RS232
Pin
Number
Signal
GE865
-
QUAD
Pad
Number
Name
Usage
1 DCD - dcd_uart B5 Data Carrier Detect Output from the GE865 that indicates the carrier
presence
2 RXD -
tx_uart A4 Transmit line *see Note Output transmit line of GE865 UART
3 TXD -
rx_uart A3 Receive line *see Note Input receive of the GE865 UART
4 DTR - dtr_uart B3 Data Terminal Ready Input to the GE865 that controls the DTE READY
condition
5 GND C2, C7, E5,
E7, G1, G3,
G4, G5, H3,
H6
Ground ground
6 DSR - dsr_uart B2 Data Set Ready Output from the GE865 that indicates the module is
ready
7 RTS -rts_uart A1 Request to Send Input to the GE865 that controls the Hardware flow
control
8 CTS - cts_uart A2 Clear to Send Output from the GE865 that controls the Hardware
flow control
9 RI - ri_uart B4 Ring Indicator Output from the GE865 that indicates the incoming
call condition
NOTE: According to V.24, RX/TX signal names are referred to the application side, therefore on
the GE865 side these signal are on the opposite direction: TXD on the application side will be
connected to the receive line (here named TXD/ rx_uart ) of the GE865 serial port and
viceversa for RX.
TIP: For a minimum implementation, only the TXD and RXD lines can be connected, the other
lines can be left open provided a software flow control is implemented.
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8.2 RS232 level translation
In order to interface the Telit GE865 with a PC com port or a RS232 (EIA/TIA-232) application a level
translator is required. This level translator must:
• invert the electrical signal in both directions;
• change the level from 0/2.8V to +15/-15V .
Actually, the RS232 UART 16450, 16550, 16650 & 16750 chipsets accept signals with lower levels on
the RS232 side (EIA/TIA-562), allowing a lower voltage-multiplying ratio on the level translator. Note
that the negative signal voltage must be less than 0V and hence some sort of level translation is
always required.
The simplest way to translate the levels and invert the signal is by using a single chip level translator.
There are a multitude of them, differing in the number of drivers and receivers and in the levels (be
sure to get a true RS232 level translator not a RS485 or other standards).
By convention the driver is the level translator from the 0-2.8V UART to the RS232 level. The receiver
is the translator from the RS232 level to 0-2.8V UART.
In order to translate the whole set of control lines of the UART you will need:
• 5 drivers
• 3 receivers
The digital input lines working at 2.8V CMOS have an absolute maximum input voltage of 3.0V;
therefore the level translator IC shall not be powered by the +3.8V supply of the module.
Instead, it must be powered from a +2.7V / +2.9V (dedicated) power supply.
This is because in this way the level translator IC outputs on the module side (i.e. GE865
inputs) will work at +3.8V interface levels, damaging the module inputs.
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An example of level translation circuitry of this kind is:
The example is done with a SIPEX SP3282EB RS232 Transceiver that could accept supply voltages
lower than 3V DC.
In this case Vin has to be set with a value compatible with the logic levels of the module. (Max
2.9V DC). In this configuration the SP3282EB will adhere to EIA/TIA-562 voltage levels instead
of RS232 (-5 ~ +5V)
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Second solution could be done using a MAXIM transceiver (MAX218) In this case the
compliance with RS232 (+-5V) is possible.
Another level adapting method could be done using a standard RS232 Transceiver (MAX3237EAI)
adding some resistors to adapt the levels on the GE865 Input lines.
NOTE: In this case has to be taken in account the length of the lines on the application to avoid
problems in case of High-speed rates on RS232.
The RS232 serial port lines are usually connected to a DB9 connector with the following layout:
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8.3 5V UART level translation
If the OEM application uses a microcontroller with a serial port (UART) that works at a voltage different
from 2.8 - 3V, then a circuitry has to be provided to adapt the different levels of the two set of signals.
As for the RS232 translation there are a multitude of single chip translators. For example a possible
translator circuit for a 5V TRANSMITTER/RECEIVER can be:
TIP: Note that the TC7SZ07AE has open drain output, therefore the resistor R2 is mandatory.
TO TELIT
MODULE
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NOTE: The UART input line TXD (rx_uart) of the GE865 is NOT internally pulled up with a resistor, so there may be
the need to place an external 47KΩ pull-up resistor, either the DTR (dtr_uart) and RTS (rts_uart) input lines are not
pulled up internally, so an external pull-up resistor of 47KΩ may be required.
NOTE: The input lines working at 2.8VCMOS can be pulled-up with 47KΩ
In case of reprogramming of the module has to be considered the use of the RESET line to start correctly the
activity.
The preferable configuration is having an external supply for the buffer.
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9 Audio Section Overview
The Base Band Chip of the GE865 Telit Module provides one audio Line usable in transmit (Uplink)
and in receive (Downlink) direction:
9.1 Microphone Paths Characteristic and Requirements
TIP: being the microphone circuitry the more noise sensitive, its design and layout must be
done with particular care. The microphone path is balanced and the OEM circuitry should be
balanced designed to reduce the common mode noise typically generated on the ground
plane. However also an unbalanced circuitry can be used for particular OEM application needs.
“Mic” differential microphone path
• line coupling AC
• line type balanced
• coupling capacitor ≥ 100nF
• differential input resistance 50kΩ
• differential input voltage ≤ 1,03V
pp
(365mV
rms
)
• microphone nominal sensitivity -45 dBV
rms
/Pa
• analog gain suggested + 20dB
• echo canceller type handset
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10 OUTPUT LINES (Speaker)
10.1 Short description
The Telit GE865 provides one audio paths in receive section.
the “Ear” lines EPN1 and EPP1 are the Differential Line-Out Drivers ; they can drive an external
amplifier or directly a 16 Ω earpiece at –12dBFS (*) ;
(*) FS : acronym of Full Scale. It is equal to 0dB, the maximum Hardware Analog Receive Gain of
BaseBand Chip.
The output is a B.T.L. type (Bridged Tie Load) and the OEM circuitry shall be designed bridged to
reduce the common mode noise typically generated on the ground plane and to get the maximum
power output from the device; however also a single ended circuitry can be designed for particular
OEM application needs.
10.2 Output Lines Characteristics
“Ear” Differential Line-out Drivers Path
• line coupling: DC
• line type: bridged
• output load resistance : ≥ 14 Ω
• internal output resistance: 4 Ω (typical)
• signal bandwidth: 150 - 4000 Hz @ -3 dB
• max. differential output voltage 1310 mV
rms
(typ, open circuit)
• differential output voltage 328mVrms /16 Ω @ -12dBFS
• SW volume level step - 2 dB
• number of SW volume steps 10
For more detailed information about audio please refer to the Audio Settings Application Note
80000NT10007a
.
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11 General Purpose I/O
The general purpose I/O pads can be configured to act in three different ways:
• input
• output
• alternate function (internally controlled)
Input pads can only be read and report the digital value (high or low) present on the pad at the read
time; output pads can only be written or queried and set the value of the pad output; an alternate
function pad is internally controlled by the GE865 firmware and acts depending on the function
implemented. For Logic levels please refer to chapter 7.
The following GPIO are available on the GE865-QUAD:
Signal I/O Function Type
Input /
output
current
Default
State
ON_OFF
state
State
during
Reset Note
GPIO_01 I/O GPIO01 Configurable GPIO CMOS 2.8V
1uA/1mA INPUT 0 0
GPIO_02 I/O GPIO02 Configurable GPIO CMOS 2.8V
1uA/1mA INPUT 0 0 Alternate function
(JDR)
GPIO_03 I/O GPIO03 Configurable GPIO CMOS 2.8V
1uA/1mA INPUT 0 0
GPIO_04 I/O GPIO04 Configurable GPIO CMOS 2.8V
1uA/1mA INPUT 0 0 Alternate function
(RF Transmission
Control)
GPIO_05 I/O GPIO05 Configurable GPIO CMOS 2.8V
1uA/1mA INPUT 0 0 Alternate function
(RFTXMON)
GPIO_06 I/O GPIO06 Configurable GPIO CMOS 2.8V
1uA/1mA INPUT 0 0 Alternate function
(ALARM)
GPIO_07 I/O GPIO07 Configurable GPIO CMOS 2.8V
1uA/1mA INPUT 0 0 Alternate function
(BUZZER)
GPIO_08 I/O GPIO08 Configurable GPIO CMOS 2.8V
1uA/1mA INPUT 0 0
GPIO_09 I/O GPIO09 Configurable GPIO CMOS 2.8V
1 1 1 Open Drain
GPIO_10 I/O GPIO10 Configurable GPIO CMOS 2.8V
1 1 1 Open Drain
Not all GPIO pads support all these three modes:
• GPIO2 supports all three modes and can be input, output, Jamming Detect Output (Alternate
function)
• GPIO4 supports all three modes and can be input, output, RF Transmission Control (Alternate
function)
• GPIO5 supports all three modes and can be input, output, RFTX monitor output (Alternate
function)
• GPIO6 supports all three modes and can be input, output, alarm output (Alternate function)
• GPIO7 supports all three modes and can be input, output, buzzer output (Alternate function)
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11.1 GPIO Logic levels
Where not specifically stated, all the interface circuits work at 2.8V CMOS logic levels.
The following table shows the logic level specifications used in the GE865 interface circuits:
Absolute Maximum Ratings -Not Functional
Parameter
Min
Max
Input level on any digital pin when on
(CMOS 2.8) -0.3V +3.1V
Input level on any digital pin when on
(CMOS 1.8) -0.3V +2.1V
Input voltage on analog pins when on
-0.3V +3.0V
Operating Range - Interface levels (2.8V CMOS)
Level
Min
Max
Input high level 2.1V 3.0V
Input low level 0V 0.5V
Output high level 2.2V 3.0V
Output low level 0V 0.35V
For 1.8V signals:
Operating Range - Interface levels (1.8V CMOS)
Level
Min
Max
Input high level 1.6V 2.0V
Input low level 0V 0.4V
Output high level 1,65V 1.85V
Output low level 0V 0.35V
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11.2 Using a GPIO Pad as INPUT
The GPIO pads, when used as inputs, can be connected to a digital output of another device and
report its status, provided this device has interface levels compatible with the 2.8V CMOS levels of the
GPIO.
If the digital output of the device to be connected with the GPIO input pad has interface levels different
from the 2.8V CMOS, then it can be buffered with an open collector transistor with a 47K pull up to
2.8V.
11.3 Using a GPIO Pad as OUTPUT
The GPIO pads, when used as outputs, can drive 2.8V CMOS digital devices or compatible hardware.
When set as outputs, the pads have a push-pull output and therefore the pull-up resistor may be
omitted.
11.4 Using the RF Transmission Control GPIO4
The GPIO4 pin, when configured as RF Transmission Control Input, permits to disable the Transmitter
when the GPIO is set to Low by the application.
In the design is necessary to add a pull up resistor (47K to PWRMON);
11.5 Using the RFTXMON Output GPIO5
The GPIO5 pin, when configured as RFTXMON Output, is controlled by the GE865 module and will
rise when the transmitter is active and fall after the transmitter activity is completed.
For example, if a call is started, the line will be HIGH during all the conversation and it will be again
LOW after hanged up.
The line rises up 300ms before first TX burst and will became again LOW from 500ms to 1sec after
last TX burst.
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11.6 Using the Alarm Output GPIO6
The GPIO6 pad, when configured as Alarm Output, is controlled by the GE865 module and will rise
when the alarm starts and fall after the issue of a dedicated AT command.
This output can be used to power up the GE865 controlling microcontroller or application at the alarm
time, giving you the possibility to program a timely system wake-up to achieve some periodic actions
and completely turn off either the application and the GE865 during sleep periods, dramatically
reducing the sleep consumption to few µA.
In battery-powered devices this feature will greatly improve the autonomy of the device.
11.7 Using the Buzzer Output GPIO7
The GPIO7 pad, when configured as Buzzer Output, is controlled by the GE865 module and will drive
with appropriate square waves a Buzzer driver.
This permits to your application to easily implement Buzzer feature with ringing tones or melody
played at the call incoming, tone playing on SMS incoming or simply playing a tone or melody when
needed by your application.
A sample interface scheme is included below to give you an idea of how to interface a Buzzer to the
GPIO7:
NOTE: To correctly drive a buzzer a driver must be provided, its characteristics depend on the Buzzer and for them
refer to your buzzer vendor.
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11.8 Indication of network service availability
The STAT_LED pin status shows information on the network service availability and Call status.
In the GE865 modules, the STAT_LED usually needs an external transistor to drive an external LED.
Therefore, the status indicated in the following table is reversed with respect to the pin status.
LED status
Device
Status
Permanently off Device off
Fast blinking
(Period 1s, Ton 0,5s) Net search / Not registered /
turning off
Slow blinking
(Period 3s, Ton 0,3s) Registered full service
Permanently on a call is active
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11.9 RTC Bypass out
The VRTC pin brings out the Real Time Clock supply, which is separate from the rest of the digital
part, allowing having only RTC going on when all the other parts of the device are off.
To this power output a backup capacitor can be added in order to increase the RTC autonomy during
power off of the battery. NO Devices must be powered from this pin.
11.10 External SIM Holder Implementation
Please refer to the related User Guide (SIM Holder Design Guides, 80000NT10001a).
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12 DAC and ADC section
12.1 DAC Converter
12.1.1 Description
The GE865 module provides a Digital to Analog Converter. The signal (named DAC_OUT) is available
on BGA Ball G7 of the GE865 module and on pin 17 of PL102 on EVK2 Board (CS1324).
The on board DAC is a 10 bit converter, able to generate a analogue value based a specific input in
the range from 0 up to 1023. However, an external low-pass filter is necessary
Min
Max
Units
Voltage range (filtered) 0 2,6 Volt
Range 0 1023 Steps
The precision is 10 bits so, if we consider that the maximum voltage is 2V, the integrated voltage could
be calculated with the following formula:
Integrated output voltage = 2 * value / 1023
DAC_OUT line must be integrated (for example with a low band pass filter) in order to obtain an
analog voltage.
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12.1.2 Enabling DAC
An AT command is available to use the DAC function.
The command is AT#DAC[=<enable>[,<value>]]
<value> - scale factor of the integrated output voltage (0..1023 - 10 bit precision)
it must be present if <enable>=1
Refer to SW User Guide or AT Commands Reference Guide for the full description of this function.
NOTE: The DAC frequency is selected internally. D/A converter must not be used during
POWERSAVING.
12.1.3 Low Pass Filter Example
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12.2 ADC Converter
12.2.1 Description
The on board A/D are 11-bit converter. They are able to read a voltage level in the range of 0÷2 volts
applied on the ADC pin input, store and convert it into 11 bit word.
Min
Max
Units
Input Voltage range 0 2 Volt
AD conversion - 11 bits
Resolution - < 1 mV
The GE865-QUAD module provides 2 Analog to Digital Converters. The input lines are:
ADC_IN1 available on Ball F5 and Pin 19 of PL102 on EVK2 Board (CS1324).
ADC_IN2 available on Ball F6 and Pin 20 of PL102 on EVK2 Board (CS1324).
12.2.2 Using ADC Converter
An AT command is available to use the ADC function.
The command is AT#ADC=1,2
The read value is expressed in mV
Refer to SW User Guide or AT Commands Reference Guide for the full description of this function.
GE865 Hardware User Guide
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12.3 Mounting the GE865 on your Board
12.3.1 General
The Telit GE865 modules have been designed in order to be compliant with a standard lead-free SMT
process.
12.3.2 Module finishing & dimensions
Lead
-
free Alloy:
Surface finishing Sn/Ag/Cu for all solder pads
Pin A1
GE865 Hardware User Guide
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12.3.3 Suggested Inhibit Area
In order to easily rework the GE865 is suggested to consider on the application a 1.5mm Inhibit area
around the module:
It is also suggested, as common rule for an SMT component, to avoid having a mechanical part of the
application in direct contact with the module.
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12.3.4 Debug of the GE865 in production
To test and debug the mounting of the GE865, we strongly recommend to foreseen test pads on the
host PCB, in order to check the connection between the GE865 itself and the application and to test
the performance of the module connecting it with an external computer. Depending by the customer
application, these pads include, but are not limited to the following signals:
• TXD
• RXD
• ON/OFF
• RESET
• GND
• VBATT
• TX_AUX
• RX_AUX
•
PWRMON
•
SERVICE
12.3.5 Stencil
Stencil’s apertures layout can be the same of the recommended footprint (1:1), we suggest a
thickness of stencil foil ≥ 120µm.
GE865 Hardware User Guide
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12.3.6 PCB pad design
Non solder mask defined” (NSMD) type is recommended for the solder pads on the PCB.
Recommendations for PCB pad dimensions
Ball pitch [mm]
2,4
Solder resist opening diameter A [mm]
1,150
Metal pad diameter B [mm]
1 ± 0.05
Placement of microvias not covered by solder resist is not recommended inside the “Solder resist
opening”, unless the microvia carry the same signal of the pad itself.
GE865 Hardware User Guide
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Holes in pad are allowed only for blind holes and not for through holes.
Recommendations for PCB pad surfaces:
Finish
Layer thickness [µm]
Properties
Electro-less Ni /
Immersion Au 3 –7 /
0.05 – 0.15 good solder ability protection, high
shear force values
The PCB must be able to resist the higher temperatures which are occurring at the lead-free process.
This issue should be discussed with the PCB-supplier. Generally, the wettability of tin-lead solder
paste on the described surface plating is better compared to lead-free solder paste.
12.3.7 Solder paste
Lead free
Solder paste
Sn/Ag/Cu
GE865 Hardware User Guide
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12.3.8 GE865 Solder reflow
The following is the recommended solder reflow profile
Profile Feature
Pb
-
Free Assembly
Average ramp-up rate (T
L
to T
P
) 3°C/second max
Preheat
– Temperature Min (Tsmin)
– Temperature Max (Tsmax)
– Time (min to max) (ts)
150°C
200°C
60-180 seconds
Tsmax to TL
– Ramp-up Rate
3°C/second max
Time maintained above:
– Temperature (TL)
– Time (tL)
217°C
60-150 seconds
Peak Temperature (Tp) 245 +0/-5°C
Time within 5°C of actual Peak
Temperature (tp) 10-30 seconds
Ramp-down Rate 6°C/second max.
Time 25°C to Peak Temperature 8 minutes max.
NOTE: All temperatures refer to topside of the package, measured on the package body surface.
N
NO
OT
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E:
:
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12.4 Packing system
The Telit GE865 modules are packaged on trays of 50 pieces each. This is especially suitable for the
GE865 according to SMT processes for pick & place movement requirements.
NOTE: These trays can withstand at the maximum temperature of 65° C.
GE865 Hardware User Guide
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12.4.1 Moisture sensibility
The level of moisture sensibility of GE865 module is “3”, in according with standard IPC/JEDEC J-STD-
020, take care all the relatives requirements for using this kind of components.
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13 Conformity Assessment Issues
The GE865-QUAD module are assessed to be conform to the R&TTE Directive as stand-alone products, so If
the module is installed in conformance with Dai Telecom installation instructions require no further evaluation
under Article 3.2 of the R&TTE Directive and do not require further involvement of a R&TTE Directive Notified
Body for the final product.
In all other cases, or if the manufacturer of the final product is in doubt then the equipment integrating the radio
module must be assessed against Article 3.2 of the R&TTE Directive.
In all cases assessment of the final product must be made against the Essential requirements of the R&TTE
Directive Articles 3.1(a) and (b), safety and EMC respectively, and any relevant Article 3.3 requirements.
The GE865-QUAD module is conforming with the following European Union Directives:
• R&TTE Directive 1999/5/EC (Radio Equipment & Telecommunications Terminal Equipments)
• Low Voltage Directive 73/23/EEC and product safety
• Directive 89/336/EEC for conformity for EMC
In order to satisfy the essential requisite of the R&TTE 99/5/EC directive, the GE865-QUAD module is
compliant with the following standards:
• GSM (Radio Spectrum). Standard: EN 301 511 and 3GPP 51.010-1
• EMC (Electromagnetic Compatibility). Standards: EN 301 489-1 and EN 301 489-7
• LVD (Low Voltage Directive) Standards: EN 60 950
In this document and the Hardware User Guide, Software User Guide all the information you may need for
developing a product meeting the R&TTE Directive is included.
The GE865-QUAD module is conforming with the following US Directives:
• Use of RF Spectrum. Standards: FCC 47 Part 24 (GSM 1900)
• EMC (Electromagnetic Compatibility). Standards: FCC47 Part 15
This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions:
(1) this device may not cause harmful interference, and
(2) this device must accept any interference received, including interference that may cause undesired
operation.
To meet the FCC's RF exposure rules and regulations:
- The system antenna(s) used for this transmitter must be installed to provide a separation distance of at
least 20 cm from all the persons and must not be co-located or operating in conjunction with any other
antenna or transmitter.
-
The system antenna(s) used for this module must not exceed 1.4dBi (850MHz) and 3.0dBi (1900MHz) for
mobile and fixed or mobile operating configurations”.
- Users and installers must be provided with antenna installation instructions and transmitter operating
conditions for satisfying RF exposure compliance.
Manufacturers of mobile, fixed or portable devices incorporating this module are advised to clarify any
regulatory questions and to have their complete product tested and approved for FCC compliance.
GE865 Hardware User Guide
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14 SAFETY RECOMMANDATIONS
READ CAREFULLY
Be sure the use of this product is allowed in the country and in the environment required. The use of
this product may be dangerous and has to be avoided in the following areas:
Where it can interfere with other electronic devices in environments such as hospitals, airports,
aircrafts, etc
Where there is risk of explosion such as gasoline stations, oil refineries, etc
It is responsibility of the user to enforce the country regulation and the specific environment regulation.
Do not disassemble the product; any mark of tampering will compromise the warranty validity.
We recommend following the instructions of the hardware user guides for a correct wiring of the
product. The product has to be supplied with a stabilized voltage source and the wiring has to be
conforming to the security and fire prevention regulations.
The product has to be handled with care, avoiding any contact with the pins because electrostatic
discharges may damage the product itself. Same cautions have to be taken for the SIM, checking
carefully the instruction for its use. Do not insert or remove the SIM when the product is in power
saving mode.
The system integrator is responsible of the functioning of the final product; therefore, care has to be
taken to the external components of the module, as well as of any project or installation issue,
because the risk of disturbing the GSM network or external devices or having impact on the security.
Should there be any doubt, please refer to the technical documentation and the regulations in force.
Every module has to be equipped with a proper antenna with specific characteristics. The antenna has
to be installed with care in order to avoid any interference with other electronic devices and has to
guarantee a minimum distance from the body (20 cm). In case of this requirement cannot be satisfied,
the system integrator has to assess the final product against the SAR regulation.
The European Community provides some Directives for the electronic equipments introduced on the
market. All the relevant information’s are available on the European Community website:
http://europa.eu.int/comm/enterprise/rtte/dir99-5.htm
The text of the Directive 99/05 regarding telecommunication equipments is available, while the
applicable Directives (Low Voltage and EMC) are available at:
http://europa.eu.int/comm/enterprise/electr_equipment/index_en.htm
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15 Document Change Log
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ISSUE#0 26/01/2009 First ISSUE# 0 - DRAFT
ISSUE#1 05/02/2009 Updated current consumptions table
ISSUE#2 15/02/2009 Updated Pinout description
ISSUE#3 18/03/2009 Updated mechanical dimensions (balls spacing),
charger description removed,
Added better explanation of pin H5 (RF) and H1 (service)
ISSUE#4 02/04/2009 Updated VBATT supply Range, DAC schematic, Conformity assessment
ISSUE#5 03/06/2009 Updated section 13 (FCC Conformity assessment)
ISSUE#5 04/06/2009 Updated section 13 (FCC Conformity assessment)