Telit Wireless Solutions GE865 Installation manual

GE865 Hardware User Guide
1vv0300799 Rev.17 – 2017-05-11

GE865 Hardware User Guide
1vv0300799 Rev.17– 2017-05-11
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved
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APPLICABILITY TABLE
PRODUCT
GE865-QUAD

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SPECIFICATIONS SUBJECT TO CHANGE WITHOUT NOTICE
Notice
While reasonable efforts have been made to assure the accuracy of this document, Telit assumes
no liability resulting from any inaccuracies or omissions in this document, or from use of the
information obtained herein. The information in this document has been carefully checked and is
believed to be entirely reliable. However, no responsibility is assumed for inaccuracies or
omissions. Telit reserves the right to make changes to any products described herein and
reserves the right to revise this document and to make changes from time to time in content
hereof with no obligation to notify any person of revisions or changes. Telit does not assume
any liability arising out of the application or use of any product, software, or circuit described
herein; neither does it convey license under its patent rights or the rights of others.
It is possible that this publication may contain references to, or information about Telit products
(machines and programs), programming, or services that are not announced in your country.
Such references or information must not be construed to mean that Telit intends to announce
such Telit products, programming, or services in your country.
Copyrights
This instruction manual and the Telit products described in this instruction manual may be,
include or describe copyrighted Telit material, such as computer programs stored in
semiconductor memories or other media. Laws in the Italy and other countries preserve for Telit
and its licensors certain exclusive rights for copyrighted material, including the exclusive right
to copy, reproduce in any form, distribute and make derivative works of the copyrighted
material. Accordingly, any copyrighted material of Telit and its licensors contained herein or in
the Telit products described in this instruction manual may not be copied, reproduced,
distributed, merged or modified in any manner without the express written permission of Telit.
Furthermore, the purchase of Telit products shall not be deemed to grant either directly or by
implication, estoppel, or otherwise, any license under the copyrights, patents or patent
applications of Telit, as arises by operation of law in the sale of a product.
Computer Software Copyrights
The Telit and 3rd Party supplied Software (SW) products described in this instruction manual
may include copyrighted Telit and other 3rd Party supplied computer programs stored in
semiconductor memories or other media. Laws in the Italy and other countries preserve for Telit
and other 3rd Party supplied SW certain exclusive rights for copyrighted computer programs,
including the exclusive right to copy or reproduce in any form the copyrighted computer
program. Accordingly, any copyrighted Telit or other 3rd Party supplied SW computer programs
contained in the Telit products described in this instruction manual may not be copied (reverse
engineered) or reproduced in any manner without the express written permission of Telit or the
3rd Party SW supplier. Furthermore, the purchase of Telit products shall not be deemed to grant
either directly or by implication, estoppel, or otherwise, any license under the copyrights,
patents or patent applications of Telit or other 3rd Party supplied SW, except for the normal
non-exclusive, royalty free license to use that arises by operation of law in the sale of a product.

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Usage and Disclosure Restrictions
License Agreements
The software described in this document is the property of Telit and its licensors. It is furnished
by express license agreement only and may be used only in accordance with the terms of such
an agreement.
Copyrighted Materials
Software and documentation are copyrighted materials. Making unauthorized copies is
prohibited by law. No part of the software or documentation may be reproduced, transmitted,
transcribed, stored in a retrieval system, or translated into any language or computer language,
in any form or by any means, without prior written permission of Telit
High Risk Materials
Components, units, or third-party products used in the product described herein are NOT fault-
tolerant and are NOT designed, manufactured, or intended for use as on-line control equipment
in the following hazardous environments requiring fail-safe controls: the operation of Nuclear
Facilities, Aircraft Navigation or Aircraft Communication Systems, Air Traffic Control, Life
Support, or Weapons Systems (High Risk Activities"). Telit and its supplier(s) specifically
disclaim any expressed or implied warranty of fitness for such High Risk Activities.
Trademarks
TELIT and the Stylized T Logo are registered in Trademark Office. All other product or service
names are the property of their respective owners.
Copyright © Telit Communications S.p.A.
Contents

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1. INTRODUCTION .........................................................................................................................................................7
1.1. SCOPE .......................................................................................................................................................................7
1.2. AUDIENCE.................................................................................................................................................................7
1.3. CONTACT INFORMATION,SUPPORT...........................................................................................................................7
1.4. DOCUMENT ORGANIZATION .....................................................................................................................................7
1.5. TEXT CONVENTIONS .................................................................................................................................................8
1.6. RELATED DOCUMENTS .............................................................................................................................................9
2. OVERVIEW ................................................................................................................................................................9
3. GE865 MECHANICAL DIMENSIONS ..........................................................................................................................11
4. GE865 MODULE CONNECTIONS...............................................................................................................................12
4.1. PIN-OUT................................................................................................................................................................12
4.1.1. BGA Balls Layout..........................................................................................................................................15
5. HARDWARE COMMANDS........................................................................................................................................16
5.1. TURNING ON THE GE865 .......................................................................................................................................16
5.2. TURNING OFF THE GE865......................................................................................................................................20
5.3. RESETTING THE GE865...........................................................................................................................................22
5.3.1. Hardware Unconditional restart ...................................................................................................................22
6. POWER SUPPLY .......................................................................................................................................................25
6.1. POWER SUPPLY REQUIREMENTS .............................................................................................................................25
6.2. POWER CONSUMPTION............................................................................................................................................26
6.2.1. Power consumption Plots ..............................................................................................................................27
6.3. GENERAL DESIGN RULES ........................................................................................................................................31
6.3.1. Electrical Design Guidelines.........................................................................................................................31
6.3.2. Thermal Design Guidelines...........................................................................................................................34
6.3.3. Power Supply PCB layout Guidelines ...........................................................................................................35
7. ANTENNA ................................................................................................................................................................36
7.1. GSM ANTENNA REQUIREMENTS ............................................................................................................................36
7.2. GSM ANTENNA -PCB LINE GUIDELINES................................................................................................................37
7.3. PCB GUIDELINES IN CASE OF FCC CERTIFICATION.................................................................................................38
7.3.1. Transmission line design ...............................................................................................................................38
7.3.2. Transmission line measurements...................................................................................................................39
7.4. GSM ANTENNA -INSTALLATION GUIDELINES........................................................................................................41
8. LOGIC LEVEL SPECIFICATIONS..................................................................................................................................42
8.1. RESET SIGNAL .........................................................................................................................................................43
9. SERIAL PORTS..........................................................................................................................................................44
9.1. MODEM SERIAL PORT.......................................................................................................................................44
9.2. RS232 LEVEL TRANSLATION ...................................................................................................................................45
9.3. UART BEHAVIOUR.................................................................................................................................................49
10. AUDIO SECTION OVERVIEW ................................................................................................................................50
10.1. ELECTRICAL CHARACTERISTICS .............................................................................................................................50
10.1.1. Input Lines.....................................................................................................................................................51

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10.1.2. Output Lines ..................................................................................................................................................51
11. GENERAL PURPOSE I/O .......................................................................................................................................52
11.1. GPIO LOGIC LEVELS...............................................................................................................................................53
11.2. USING A GPIO PAD AS INPUT ...............................................................................................................................55
11.3. USING A GPIO PAD AS OUTPUT ...........................................................................................................................55
11.4. USING THE RF TRANSMISSION CONTROL GPIO4....................................................................................................55
11.5. USING THE RFTXMON OUTPUT GPIO5 ................................................................................................................56
11.6. USING THE ALARM OUTPUT GPIO6........................................................................................................................56
11.7. USING THE BUZZER OUTPUT GPIO7.......................................................................................................................56
11.8. INDICATION OF NETWORK SERVICE AVAILABILITY..................................................................................................57
11.9. RTC BYPASS OUT ...................................................................................................................................................58
11.10. EXTERNAL SIM HOLDER IMPLEMENTATION ......................................................................................................58
12. DAC AND ADC SECTION .......................................................................................................................................59
12.1. DAC CONVERTER ...................................................................................................................................................59
12.1.1. Description ....................................................................................................................................................59
12.1.2. Enabling DAC ...............................................................................................................................................60
12.1.3. Low Pass Filter Example...............................................................................................................................60
12.2. ADC CONVERTER ...................................................................................................................................................61
12.2.1. Description ....................................................................................................................................................61
12.2.2. Using ADC Converter ...................................................................................................................................61
13. MOUNTING THE GE865 ON YOUR BOARD........................................................................................................... 62
13.1. GENERAL ................................................................................................................................................................62
13.2. MODULE FINISHING &DIMENSIONS ........................................................................................................................62
13.3. RECOMMENDED FOOT PRINT FOR THE APPLICATION................................................................................................63
13.4. DEBUG OF THE GE865 IN PRODUCTION...................................................................................................................64
13.5. STENCIL ..................................................................................................................................................................64
13.6. PCB PAD DESIGN ....................................................................................................................................................65
13.7. SOLDER PASTE ........................................................................................................................................................66
13.7.1. GE865 Solder reflow .....................................................................................................................................67
14. PACKING SYSTEM ................................................................................................................................................69
14.1. PACKING ON TRAY ..................................................................................................................................................69
14.1.1. Tray detail .....................................................................................................................................................70
14.2. PACKAGING ON REEL ..............................................................................................................................................71
14.2.1. Carrier Tape detail........................................................................................................................................71
14.2.2. Reel detail......................................................................................................................................................72
14.2.3. Packaging detail............................................................................................................................................73
14.3. MOISTURE SENSIBILITY...........................................................................................................................................73
15. SAFETY RECOMMANDATIONS.............................................................................................................................74
16. DOCUMENT HISTORY ..........................................................................................................................................75

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1. Introduction
1.1. Scope
The aim of this document is the description of some hardware solutions useful for developing a
product with the Telit GE865 module.
1.2. Audience
This document is intended for Telit customers, who are integrators, about to implement their
applications using our GE865 modules.
1.3. Contact Information, Support
For general contact, technical support, to report documentation errors and to order manuals,
contact Telit’s Technical Support Center (TTSC) at:
[e-mail]
[e-mail]
[e-mail]
[e-mail]
Alternatively, use:
http://www.telit.com/en/products/technical-support-center/contact.php
For detailed information about where you can buy the Telit modules or for recommendations on
accessories and components visit:
http://www.telit.com
To register for product news and announcements or for product questions contact Telit’s
Technical Support Center (TTSC).
Our aim is to make this guide as helpful as possible. Keep us informed of your comments and
suggestions for improvements.
Telit appreciates feedback from the users of our information.
1.4. Document Organization

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This document contains the following chapters:
Chapter 1: “Introduction” provides a scope for this document, target audience, contact and
support information, and text conventions.
Chapter 2: “Overview” provides an overview of the document.
Chapter 3: “GE865 Mechanical Dimensions”
Chapter 4: “GE865 Module Connections” deals with the pin out configuration and layout.
Chapter 5: “Hardware Commands” How to operate on the module via hardware.
Chapter 6: “Power supply” Power supply requirements and general design rules.
Chapter 7: “Antenna” The antenna connection and board layout design are the most important
parts in the full product design.
Chapter 8: “Logic Level specifications” Specific values adopted in the implementation of logic
levels for this module.
Chapter 9: “Serial ports” The serial port on the Telit GE865 is the core of the interface between
the module and OEM hardware
Chapter 10: “Audio Section overview” Refers to the audio blocks of the Base Band Chip of the
GE865 Telit Modules.
Chapter 11: “General Purpose I/O” How the general purpose I/O pads can be configured.
Chapter 12 “DAC and ADC Section” Deals with these two kind of converters.
Chapter 13: “Mounting the GE865 on the application board” Recommendations and specifics on
how to mount the module on the user’s board.
1.5. Text Conventions
Danger – This information MUST be followed or catastrophic equipment failure or bodily
injury may occur.

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Caution or Warning – Alerts the user to important points about integrating the module, if
these points are not followed, the module and end user equipment may fail or malfunction.
Tip or Information – Provides advice and suggestions that may be useful when integrating
the module.
All dates are in ISO 8601 format, i.e. YYYY-MM-DD.
1.6. Related Documents
•Telit's GSM/GPRS Family Software User Guide, 1vv0300784
•Audio settings application note , 80000NT10007a
•Digital Voice Interface Application Note, 80000NT10004a
•GE865 Product description,
•SIM Holder Design Guides, 80000NT10001a
•AT Commands Reference Guide, 80000ST10025a
•Telit EVK2 User Guide, 1vv0300704
2. Overview
The aim of this document is the description of some hardware solutions useful for developing a
product with the Telit GE865 module.

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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 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:
(The integration of the GSM/GPRS GE865 cellular module within user application shall be
done according to the design rules described in this manual.
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.

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3. GE865 Mechanical Dimensions
The GE865-QUAD overall dimensions are:
•Length: 22 mm
•Width: 22 mm
•Thickness: 3.0 mm
•Weight: 3,2 g

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4. GE865 module connections
4.1. 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
TX_AUX
O
Auxiliary UART (TX Data to DTE)
CMOS 2.8V
E1
RX_AUX
I
Auxiliary UART (RX Data from DTE)
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 Internal pull-up
H2 VRTC AI/O 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
E2 PWRMON O Power ON Monitor CMOS 2.8V
H5
Antenna
O
Antenna output – 50 Ω
RF
H1 Service I
Service pin can be used to upgrade the
module from ASC1 as a alternative to default
upgrading procedure using ASC0
Any pull-up/down
are required CMOS 2.8V
GPIO

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Ball Signal I/O Function Note Type
D3 GPIO_01 / DVI_WA0 I/O
GPIO01 Configurable GPIO / Digital Audio
Interface (WA0)
CMOS 2.8V
D2
GPIO_02 / JDR /
DVI_RX
I/O
GPIO02 I/O pin / Jammer Detect Report / Digital
Audio Interface (RX)
CMOS 2.8V
E4 GPIO_03 / DVI_TX I/O
GPIO03 GPIO I/O pin // Digital Audio Interface
(TX)
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 / DVI_CLK I/O
GPIO08 Configurable GPIO / Digital Audio
Interface (CLK)
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 -
WARNING:Reserved pins must not be connected.

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NOTE:
If not used, almost all pins should be left disconnected. The only exceptions are the following
pins:
RTS pin should be connected to the GND (on the module side) if flow control is not used
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
D1
TXD_AUX
E1
RXD_AUX
H1
Service

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4.1.1. BGA Balls Layout
TOP VIEW
A B C D E F G H
1 C105 / RTS ON_OFF RESET* TX_AUX RX_AUX VBATT GND SERVICE
2 C106/CTS C107/DSR GND GPIO_02 /
DVI_RX PWRMON VBATT_P A GPIO_05 VRTC
3 C103_TXD C108/DTR - GPIO_01 /
DVI_WA0 GPIO_10 VBATT_P A GND GND
4 C104/RXD C125/RING - GPIO_08 /
DVI_CLK
GPIO_03 /
DVI_TX 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 CARD
ANTENNA
UARTS
DAC and ADC
MISCELLANEOUS
GPIO
POWER SUPPLY VBATT
POWER SUPPLY GND
RESERVED

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5. Hardware Commands
5.1. Turning ON the GE865
To turn on the GE865 the pad ON# must be tied low for at least 1 second and then released.
When the power supply voltage is lower than 3.4V the pad ON# must be tied low at least 5
seconds.
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 labelled 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.
NOTE:
It is mandatory to avoid sending data to the serial ports during the first 200mS of the module
start-up.
A flow chart showing the proper turn on procedure is displayed below:

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NOTE:
In order to avoid a back powering effect it is recommended to avoid having any HIGH logic
level signal applied to the digital pins of the GE865 when the module is powered off or during
an ON/OFF transition.
Modem ON Proc.
Y
Y
Modem RESET
Proc.
AT init sequence.
Start AT CMD.
N
PWMON = ON?
PWMON = ON?
AT answer in 1Sec ?
N
Y
N
Delay 1s
DELAY= 900mSec
ON_OFF = LOW
Delay = 5 Sec
ON_OFF = HIGH
Enter AT<CR>

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A flow chart showing the AT command managing procedure is displayed below:
For example:
AT answer in
1Sec ?
Y
N
Start AT CMD.
DELAY= 300mSec
Enter AT<CR>
AT init sequence.
Modem ON Proc.
Disconnect VBatt

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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:

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5.2. Turning OFF the GE865
Turning off of the device can be done in two ways:
•via AT command (see GE865 Software User Guide, AT#SHDN)
•by tying low pin ON#
Either ways, the device issues a detach request to network informing that the device will not be
reachable any more.
To turn OFF the GE865 the pad ON# must be tied low for at least 2 seconds and then released.
A Pulse duration less than 2 seconds should also start the power off procedure, but this is not
guaranteed.
The same circuitry and timing for the power on must be used.
The device shuts down after the release of the ON# pad.
TIP:
To check if the device has been powered off, the hardware line PWRMON must be monitored.
The device is powered off when PWRMON goes low.
NOTE:
In order to avoid a back powering effect it is recommended to avoid having any HIGH logic
level signal applied to the digital pins of the GE865 when the module is powered off or during
an ON/OFF transition.