Telit Wireless Solutions GL865 QUAD, GL865 DUAL Hardware User's Manual

GL865 Hardware User Guide
1vv0300910 Rev.3 – 2011-10-03
GL865 Hardware User Guide
1vv0300910 Rev.3 – 2011-10-03
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 2 of 71
APPLICABILITY TABLE
PRODUCT
GL865 QUAD
GL865 DUAL
GL865 Hardware User Guide
1vv0300910 Rev.3 – 2011-10-03
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 3 of 71
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.
GL865 Hardware User Guide
1vv0300910 Rev.3 – 2011-10-03
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 4 of 71
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 fault­tolerant 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. 2011.
GL865 Hardware User Guide
1vv0300910 Rev.3 – 2011-10-03
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 5 of 71
Contents
1. INTRODUCTION ........................................................................................................................................................... 7
1.1. SCOPE ....................................................................................................................................................................... 7
1.2. AUDIENCE ................................................................................................................................................................. 7
1.3. CONTACT INFORMATION, SUPPORT ........................................................................................................................... 7
1.4. DOCUMENT ORGANIZATION ..................................................................................................................................... 8
1.5. TEXT CONVENTIONS ................................................................................................................................................. 9
1.6. RELATED DOCUMENTS ............................................................................................................................................. 9
2. OVERVIEW .................................................................................................................................................................. 10
3. GL865 MECHANICAL DIMENSIONS ..................................................................................................................... 11
4. GL865 MODULE CONNECTIONS ........................................................................................................................... 12
4.1. PIN-OUT ................................................................................................................................................................ 12
4.2. PIN LAYOUT ............................................................................................................................................................ 15
5. HARDWARE COMMANDS ....................................................................................................................................... 16
5.1. AUTO-TURNING ON THE GL865 ............................................................................................................................. 16
5.2. TURNING OFF THE GL865 ...................................................................................................................................... 18
5.3. RESETTING THE GL865 ........................................................................................................................................... 20
5.3.1. Hardware Unconditional restart ................................................................................................................... 20
6. POWER SUPPLY ......................................................................................................................................................... 22
6.1. POWER SUPPLY REQUIREMENTS ............................................................................................................................. 22
6.2. POWER CONSUMPTION ............................................................................................................................................ 22
6.3. GENERAL DESIGN RULES ........................................................................................................................................ 23
6.3.1. Electrical Design Guidelines ......................................................................................................................... 24
6.3.2. Thermal Design Guidelines ........................................................................................................................... 28
6.3.3. Power Supply PCB layout Guidelines ........................................................................................................... 29
7. ANTENNA ..................................................................................................................................................................... 30
7.1. GSM ANTENNA REQUIREMENTS ............................................................................................................................ 30
7.1.1. GL865 Antenna – PCB line Guidelines ......................................................................................................... 30
7.2. PCB GUIDELINES IN CASE OF FCC CERTIFICATION ................................................................................................. 31
7.2.1. Transmission line design ............................................................................................................................... 31
7.2.2. Transmission line measurements ................................................................................................................... 32
7.3. GSM ANTENNA - INSTALLATION GUIDELINES ........................................................................................................ 35
8. LOGIC LEVEL SP ECIFICATIONS .......................................................................................................................... 36
8.1. RESET SIGNAL ......................................................................................................................................................... 37
9. SERIAL PORTS ........................................................................................................................................................... 38
9.1. MODEM SERIAL PORT ....................................................................................................................................... 38
9.2. RS232 LEVEL TRANSLATION ................................................................................................................................... 40
9.3. ....................................................................................................................................................................................... 42
9.4. 5V UART LEVEL TRANSLATION ............................................................................................................................. 43
10. AUDIO SECTION OVERVIEW ............................................................................................................................ 45
10.1. ELECTRICAL CHARACTERISTICS ............................................................................................................................. 48
GL865 Hardware User Guide
1vv0300910 Rev.3 – 2011-10-03
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 6 of 71
10.1.1. Input Lines ..................................................................................................................................................... 48
10.1.2. Output Lines .................................................................................................................................................. 49
11. GENERAL PURPOSE I/O ...................................................................................................................................... 50
11.1. GPIO LOGIC LEVELS ............................................................................................................................................... 51
11.2. USING A GPIO PAD AS INPUT ............................................................................................................................... 51
11.3. USING A GPIO PAD AS OUTPUT ........................................................................................................................... 52
11.4. USING THE RF TRANSMISSION CONTROL GPIO4 .................................................................................................... 52
11.5. USING THE RFTXMON OUTPUT GPIO5 ................................................................................................................ 52
11.6. USING THE ALARM OUTPUT GPIO6 ........................................................................................................................ 53
11.7. USING THE BUZZER OUTPUT GPIO7 ....................................................................................................................... 53
11.8. MAGNETIC BUZZER CONCEPTS ............................................................................................................................... 53
1.1.1 Short Description ................................................................................................................................................... 53
11.8.1. Frequency Behaviour .................................................................................................................................... 54
11.8.2. Power Supply Influence ................................................................................................................................. 54
11.8.3. Working Current Influence ............................................................................................................................ 55
11.9. STAT LED INDICATION OF NETWORK SERVICE AVAILABILITY............................................................................... 55
11.10. SIMIN DETECT FUNCTION .................................................................................................................................. 57
11.11. RTC BYPASS OUT ............................................................................................................................................... 58
11.12. 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 Converte r ................................................................................................................................... 61
12.3. DEBUG OF THE GL865 IN PRODUCTION ................................................................................................................... 62
13. MOUNTING THE GL865 ON YOUR BOARD .................................................................................................... 63
13.1. GENERAL ................................................................................................................................................................ 63
13.2. MODULE FINISHING & DIMENSIONS ........................................................................................................................ 63
13.3. RECOMMENDED FOOT PRINT FOR THE APPLICATION ................................................................................................ 64
13.4. SOLDER PASTE ........................................................................................................................................................ 65
13.4.1. GL865 Solder reflow ..................................................................................................................................... 65
14. PACKING SYSTEM ................................................................................................................................................ 67
14.1. MOISTURE SENSIBILITY ........................................................................................................................................... 68
15. CONFORMITY ASSESSMENT ISSUES .............................................................................................................. 69
16. SAFETY RECOMMANDATIONS ......................................................................................................................... 70
17. DOCUMENT HISTO RY ......................................................................................................................................... 71
GL865 Hardware User Guide
1vv0300910 Rev.3 – 2011-10-03
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 7 of 71
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 GL865 module.
1.2. Audience
This document is intended for Telit customers, who are integrators, about to implement their applications using our GL865 modules.
1.3. Contact Information, Support
For general contact, technical support, to report documentation errors and to order manuals, contact Telit’s Technical Suppor t Center ( TTSC) at :
TS-EMEA@telit.com TS-NORTHAMERICA@telit.com TS-LATINAMERICA@telit.com TS-APAC@telit.com
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.
GL865 Hardware User Guide
1vv0300910 Rev.3 – 2011-10-03
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 8 of 71
1.4. Document Organization
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: “GL865 Mechanical Dimensions”
Chapter 4: “GL865 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 GL865 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
GL865 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 GL865 on the application board”
Recommendations and specifics on
how to mount the module on the user’s board.
GL865 Hardware User Guide
1vv0300910 Rev.3 – 2011-10-03
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 9 of 71
1.5. Text Conventions
Danger – This information MUST be followed or catastrophic equipment failure or bodily injury may occur.
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
GL865 Product description, 80370ST10080a
SIM Holder Design Guides, 80000NT10001a
AT Commands Reference Guide, 80000ST10025a
Telit EVK2 User Guide, 1vv0300704
GL865 Hardware User Guide
1vv0300910 Rev.3 – 2011-10-03
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 10 of 71
2. Overview
The aim of this document is the description of some hardware solutions useful for developing a product with the Telit GL865 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 GL865 module. For further hardware details that may not be explained in this document refer to the Telit GL865 Product De scri pti on document where all the hardware information is reported.
NOTICE:
The integration of the GSM/GPRS GL865 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.
GL865 Hardware User Guide
1vv0300910 Rev.3 – 2011-10-03
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 11 of 71
3. GL865 Mechanical Dim ensions
The GL865 overall dimensions are:
Length: 24.4 mm
• Width: 24.4 mm
• Thickness: 2.7 mm
• Weight 2.48 g
GL865 Hardware User Guide
1vv0300910 Rev.3 – 2011-10-03
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 12 of 71
4. GL865 module connections
4.1. PIN-OUT
Pad Signal I/O Function Note Type
Audio
20
EAR- AO Earphone signal output, phase - Audio
21
EAR+ AO Earphone signal output , phase + Audio
22
MIC- AI Mic.signal input; phase- Audio
24
MIC+ AI Mic.signal input; phase+ Audio
23
AGND - Analog Ground -
SIM card interface
9
SIMVCC - External SIM signal – Power supply for the SIM 1,8 / 3V
10
SIMRST O External SIM signal – Reset 1,8 / 3V
11
SIMCLK O External SIM signal – Clock 1,8 / 3V
12
SIMIO I/O External SIM signal – Data I/O
4.7K Pull up
1,8 / 3V
X
All GPI0
can be
program
med
SIMIN I
Presence SIM input
(See para 11.9)
CMOS 2.8V
Trace
44
RX_AUX I Auxiliary UART (RX Data) CMOS 2.8V
45
TX_AUX O Auxiliary UART (TX Data) CMOS 2.8V
Prog. / Data + HW Flow Control
1
C109/DCD/GPO O
Output for Data carrier detect signal (DCD) to DTE
/ GP output
CMOS 2.8V
2
C125/RING/GPO O
Output for Ring indicator signal (RI) to DTE
/ GP output
CMOS 2.8V
3
C107/DSR/GPO O
Output for Data set ready signal (DSR) to DTE
/ GP output
CMOS 2.8V
4
C108/DTR/GPI I
Input for Data terminal ready signal (DTR) from DTE
/ GP input
CMOS 2.8V
5
C105/RTS/GPI I
Input for Request to send signal (RTS) from DTE
/ GP input
CMOS 2.8V
6
C106/CTS/GPO O
Output for Clear to send si gnal (CTS) to DTE
/ GP output
CMOS 2.8V
7
C103/TXD I Serial data input (TXD) from DTE CMOS 2.8V
8
C104/RXD O Serial data output to DTE CMOS 2.8V
DAC and ADC
13
ADC_IN1 AI Analog/Digit al converter input A/D
14
ADC_IN2 AI Analog/Digit al converter input A/D
15
DAC_OUT AO Digital/Analog converter output D/A
Miscellaneous Functions
30
VRTC AO VRTC Backup Power
47
RESET* I Reset input CMOS 1.8V
43
V_AUX / PWRMON O
2.8V stabilized output Imax=100mA
/ Power ON monitor
Power Out 2.8V
GL865 Hardware User Guide
1vv0300910 Rev.3 – 2011-10-03
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 13 of 71
Pad Signal I/O Function Note Type
34
Antenna O Antenna output – 50 RF
GPIO
42
GPIO_01 / DVI_WA0 I/O
GPIO01 Configurable GPIO / Digital Audio Interface (WA0)
CMOS 2.8V
41
GPIO_02 / JDR /
DVI_RX
I/O
GPIO02 Configurable GPIO / Jammer Det ect Report
/ Digital Audio Interface (RX)
CMOS 2.8V
40
GPIO_03 / DVI_TX I/O
GPIO03 Configurable GPIO
/ Digital Audio Interface (TX)
CMOS 2.8V
39
GPIO_04 / TX Disable
/ DVI_CLK
I/O
GPIO04 Configurable GPIO / TX Disable input / Digital Audio Interface (CLK)
CMOS 2.8V
29
GPIO_05 / RFTXMON I/O
GPIO05 Configurable GPIO
/ Transmitter ON monitor
CMOS 2.8V
28
GPIO_06 / ALARM I/O
GPIO06 Configurable GPIO
/ ALARM
CMOS 2.8V
27
GPIO_07 / BUZZER I/O
GPIO07 Configurable GPIO / Buzzer
CMOS 2.8V
26
GPIO_08 / STAT_LED I/O
GPIO08 Configurable GPIO / STAT LED
CMOS 2.8V
Power Supply
38
VBATT - Main power supply (Baseband) Power
37
VBATT_PA - Main power supply (Radio PA) Power
23
AGND - AF Signal Ground (see audio section) AF Signal
32
GND - Ground Power
33
GND - Ground Power
35
GND - Ground Power
36
GND - Ground Power
46
GND - Ground Power
RESERVED
48
-
16
-
17
-
18
-
19
-
25
-
31
-
WARNING:
Reserved pins must not be connected.
NOTE:
GL865 Hardware User Guide
1vv0300910 Rev.3 – 2011-10-03
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 14 of 71
If not used, almost all pins should be left disconnected. The only exceptions are the following pins:
pin
signal
38, 37
VBATT & VB ATT_PA
32, 33, 35, 36, 46
GND
23
AGND
7
TXD
8 RXD
5
RTS
43
V_AUX / PWRMON
47
RESET*
45
TX_AUX
44
RX_AUX
GL865 Hardware User Guide
1vv0300910 Rev.3 – 2011-10-03
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 15 of 71
4.2. Pin Layout
TOP VIEW
NOTE:
The pin defined as NC/RFU has to be considered RESERVED and don’t connect on any pin in the application.
GL865 Hardware User Guide
1vv0300910 Rev.3 – 2011-10-03
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 16 of 71
5. Hardware Commands
5.1. Auto-Turning ON the GL865
To Auto-turn on the GL865, the power supply must be applied on the power pins VBATT and VBATT_PA, after 1000 m-seconds, the
V_AUX / PWRMON pin will be at the high logic level
and the module can be consider fully operating.
When the power supply voltage is lower than 3.4V, after 5000 m-seconds, the
V_AUX /
PWRMON
pin will be at the high logic level and the module can be consider fully operating.
The following flow chart shows the proper turn on procedure:
Modem ON Proc
.
PWR supply = ON?
Y
Delay 1s - 5s for Low
Voltage Operating
Y
Modem Reset Proc.
AT init sequence
.
N
Start AT CMD
.
N
PWMON = ON?
Y
PWMON = ON?
Delay 300mS
Enter AT<CR>
AT answer in
1second ?
N
Y
N
Delay 1s
GL865 Hardware User Guide
1vv0300910 Rev.3 – 2011-10-03
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 17 of 71
NOTE:
The power supply on the pins VBATT and VBATT_PA must be applied at the same time or for the special application in the first apply the VBATT_PA and in second time apply VBATT, never vice versa in this case can be damage the unit.
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 GL865 when the module is powered OFF or during an ON/OFF transition.
A flow chart showing the AT command managing procedure is displayed b elow:
Modem ON Proc.
Disconnect PWR
supply
AT init
sequence.
Delay 300mS
Enter AT<CR>
AT answer in
1second ?
Y
N
Start AT CMD
.
GL865 Hardware User Guide
1vv0300910 Rev.3 – 2011-10-03
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 18 of 71
5.2. Turning OFF the GL865
Turning off of the device can be done in two ways:
General turn OFF
Processor turn OFF
General turn OFF – disconnect the power supply from the both power pins VBATT and VBATT_PA at the same time. In this case all parts of the module are in OFF condition, any power consumption is present. Processor turn OFF – disconnect the power supply only from the power pin VBATT, the power pin VBATT_PA can be connected to power supply, in this case a low, typical 2uA max 20uA, power consumption is present. Before any of both OFF procedure will be applied, the AT#SYSHALT AT command must be send (see AT Commands Reference Guide, 80000ST10025a), after the OK response message, check the
V_AUX / PWRMON pin, when the logic level is low the module can be consider fully
not operating and at this moment is possible disconnect the Power Supply. The following flow chart shows the proper turnoff procedure:
GL865 Hardware User Guide
1vv0300910 Rev.3 – 2011-10-03
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 19 of 71
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 GL865 when the module is powered OFF or during an ON/OFF transition.
Modem OFF
Proc.
PWRMON = OFF?
Place AT command
AT#SYSHALT
N
Disconnect PWR
supply
Y
Disconnect PWR
supply
Wait
PWRMON =OFF
or
15s timeout
Modem ON Proc
.
Delay 1.5s
GL865 Hardware User Guide
1vv0300910 Rev.3 – 2011-10-03
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 20 of 71
5.3. Resetting the GL865
5.3.1. Hardware Uncondit ional restar t
WARNING:
The hardware unconditional Restart must not be used during normal operation of the device since it does not detach the device from the network. It shall be kept as an emergency exit procedure to be done in the rare case that the device gets stacked waiting for some network or SIM responses.
To unconditionally reboot the GL865, the pad RESET* must be tied low for at least 200 milliseconds and then released.
NOTE: Do not 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 GL865 power regulator and improper functioning of the module. The line RESET* must b e connected only in open collector configuration; the transistor must be connected as close as possible to the RESET* pin.
TIP: The unconditional hardware restart must always be implemented on the boards and the software
must use it as an emergency exit procedure.
A simple circuit to do it is:
GL865 Hardware User Guide
1vv0300910 Rev.3 – 2011-10-03
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 21 of 71
In the following flow chart is detailed the proper restart procedure:
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 GL865 when the module is powered OFF or during an ON/OFF transition.
Modem Reset
Proc.
Reset = LOW
Delay 200ms
Reset = HIGH
PWRMON =
OFF
Delay 1s
Start AT CMD
.
Modem ON
Proc.
Delay 1,5s
Y
N
Disconnect PWR
supply
GL865 Hardware User Guide
1vv0300910 Rev.3 – 2011-10-03
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 22 of 71
6. 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.
6.1. Power Supply Requirements
The external power supply must be connected to VBATT & VBATT_PA signals and must fulfill the following require ments:
POWER SUPPLY
Nominal Supply Voltage
3.8 V
Normal Operating Voltage Range
3.4 V÷ 4.20 V
Extended Operating Voltage Range
3.22 V÷ 4.50 V
NOTE:
The Operating Voltage Range MUST never be exceeded; care must be taken in order to fulfil 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.
NOTE:
When the power supply voltage is lower than 3.4V, after 4000 m-seconds, the V_AUX /
PWRMON
pin will be at the high logic level and the module can be consider fully operating. See
para 6.1
.
6.2. Power Consumption
The GL865 power consumptions are:
Loading...
+ 49 hidden pages