Novatel Wireless EDG0208 Operators Guide
Integration Guide:
EDG0208IG001
Enfora Enabler IIE Quad-Band
GSM/GPRS/EGPRS Modem
Integration Guide
Version 1.00
Integration Guide
Draft
Document Title: Enfora Enabler EDG0208 Quad Band GSM/GPRS/EGPRS Modem
Integration Guide
Version: Draft
Date: 05/26/2009
Status: Draft
Document Control ID: EDG0208IG001
General
All efforts have been made to ensure the accuracy of material provided in this document at
the time of release. However, the items described in this document are subject to continuous
development and improvement. All specifications are subject to change without notice and
do not represent a commitment on the part of Enfora, Inc. Enfora, Inc. will not be responsible
for any loss or damages incurred related to the use of information contained in this document.
This product is not intended for use in life support appliances, devices or systems where a
malfunction of the product can reasonably be expected to result in personal injury. Enfora,
Inc. customers using, integrating, and/or selling this product for use in such applications do so
at their own risk and agree to fully indemnify Enfora, Inc. for any damages resulting from
illegal use or resale.
Copyright
Complying with all applicable copyright laws is the responsibility of the user. Without limiting
the rights under copyright, no part of this document may be reproduced, stored in or
introduced into a retrieval system, or transmitted in any form or by any means (electronic,
mechanical, photocopying, recording or otherwise), or for any purpose, without the express
written permission of Enfora, Inc.
Enfora may have patents, patent applications, trademarks, copyrights or other intellectual
property rights covering subject matter in this document. Except as expressly provided in any
written license agreement from Enfora, the furnishing of this document does not give you any
license to these patents, trademarks, copyrights or other intellectual property.
©2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 Enfora, Inc. All rights reserved.
Enabler and Spider are either registered trademarks or trademarks of Enfora, Inc. in the
United States.
.
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Table of Contents
1.0 SAFETY PRECAUTIONS.................................................. 1
1.1 IMPORTANT SAFETY INFORMATION ..................................................................................................................... 1
2.0 REGULATORY COMPLIANCE FCC ............................. 1
2.1 INTEGRATION CONSIDERATIONS AND
INSTALLATION REQUIREMENTS ........................................ 1
2.2 DISCLAIMER ..................................................................... 2
3.0 MANUAL OVERVIEW ...................................................... 4
3.1 REFERENCE DOCUMENTS .................................................................................................................................... 4
3.1.1 ENFORA ENABLER EDG0208 PRODUCT DOCUMENTATION ............................................................................. 4
3.1.2 GSM DEVICE SPECIFICATIONS: WWW.3GPP.ORG ............................................................................................. 5
3.1.3 FEDERAL COMMUNICATIONS COMMISSION (FCC) .......................................................................................... 5
3.1.4 FCC OFFICE OF ENGINEERING AND TECHNOLOGY (OET) ............................................................................... 5
3.1.5 INDUSTRY CANADA ........................................................................................................................................ 5
3.1.6 ENVIRONMENTAL REGULATIONS .................................................................................................................... 5
3.1.7 MECHANICAL SPECIFICATIONS ....................................................................................................................... 5
3.1.8 RF AND EMI SPECIFICATIONS ........................................................................................................................ 5
4.0 INTRODUCTION ............................................................... 6
4.1 PRODUCT OVERVIEW .......................................................................................................................................... 6
4.2 KEY FEATURES OF THE GSM/GPRS OEM MODULE ........................................................................................... 6
4.3 PROVIDING MULTI-BAND OPERATION ................................................................................................................ 7
4.4 WIRELESS DATA APPLICATION POSSIBILITIES ..................................................................................................... 7
4.5 GENERAL DESIGN GUIDELINES FOR UTILIZING ENFORA GSM MODULES ............................................................... 8
4.6 ADVANCED TIPS FOR AN RF FRIENDLY LAYOUT .................................................................................................. 9
4.7 AUDIO REFERENCE DESIGN .............................................................................................................................. 13
5.0 TECHNICAL SPECIFICATIONS .................................. 15
5.1 ENABLER EDG0208 MODULE BLOCK DIAGRAM .............................................................................................. 15
5.2 DETAILED PRODUCT SPECIFICATIONS ............................................................................................................... 16
5.3 OPERATING POWER .......................................................................................................................................... 17
5.3.1 GSM Operating Power ............................................................................................................................ 17
5.3.2 GPRS Operating Power .......................................................................................................................... 17
5.3.3 EGPRS Operating Power ........................................................................................................................ 18
5.3.4 Transmit Power ....................................................................................................................................... 18
5.3.5 Receiver Sensitivity ................................................................................................................................. 18
6.0 MECHANICAL ................................................................. 19
6.1 ENABLER II-E MOUNTING TO HOST BOARD (REFERENCE) ................................................................................ 25
6.2 I/O CONNECTOR ............................................................................................................................................... 26
6.3 RF CONNECTION .............................................................................................................................................. 26
6.4 I/O SIGNAL CONNECTOR ON THE ENFORA ENABLER EDG0208 MODULE .......................................................... 27
6.4.1 I/O Connector Pin Assignments .............................................................................................................. 27
6.5 CIRCUIT PROTECTION ....................................................................................................................................... 28
6.6 ANTENNA ......................................................................................................................................................... 28
6.7 CONTROL CONNECTOR SIGNAL DESCRIPTIONS AND FUNCTIONS ........................................................................ 29
6.7.1 Input Power ............................................................................................................................................. 29
6.7.2 Ring Indicate ........................................................................................................................................... 30
6.7.3 Radio Power/Reset (Pin 22) .................................................................................................................... 31
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6.7.4 Using the Power Control Signal ............................................................................................................. 31
6.7.5 Serial Interface (9 Pin I/F) (See table in section 6.4.1 I/O Connector Pin Assignments) ........................ 32
6.7.6 Analog-To-Digital Input .......................................................................................................................... 33
6.7.7 Handset Microphone Input ...................................................................................................................... 33
6.7.8 Microphone Bias Output ......................................................................................................................... 33
6.7.9 Handset Speaker Output .......................................................................................................................... 33
6.7.10 Headset Microphone Input ...................................................................................................................... 33
6.7.11 Headset Speaker Output .......................................................................................................................... 34
1.1.1. Maximum Swing ...................................................................................................................................... 34
6.7.12 Audio Design Note .................................................................................................................................. 34
6.7.13 Transmit Active Output (Pin-37) ............................................................................................................. 36
6.8 SUBSCRIBER IDENTITY MODULE (SIM) CARRIER .............................................................................................. 36
6.8.1 SIM Integration for the Enfora Enabler EDG0208 Module .................................................................... 36
6.8.2 Using a Remote SIM with the Enfora Enabler EDG0208 Module .......................................................... 36
6.8.3 Remote SIM Component Information ...................................................................................................... 37
7.0 MODES OF OPERATION ............................................... 38
7.1 ENABLING THE TRANSMISSION MODES FOR THE GSM/GPRS/EGPRS SERVICES .............................................. 38
7.2 VOICE COMMUNICATION .................................................................................................................................. 38
7.3 CIRCUIT-SWITCHED DATA ................................................................................................................................ 38
7.4 SMS: SHORT MESSAGE SERVICES .................................................................................................................... 39
7.5 SMS FEATURES SUPPORTED BY THE ENFORA ENABLER EDG0208 MODULE .................................................... 39
8.0 SIM OPERATION ............................................................. 40
8.1 PROVISIONING THE SIM ................................................................................................................................... 40
8.2 GSM SERVICES SUPPORTED BY THE ENFORA ENABLER EDG0208 MODULE ..................................................... 40
8.3 GPRS SERVICES SUPPORTED BY THE ENFORA ENABLER EDG0208 MODULE.................................................... 40
8.4 EGPRS SERVICES SUPPORTED BY THE ENFORA ENABLER EDG0208 MODULE ................................................. 40
8.5 SELECTING THE MODES OF OPERATION............................................................................................................. 41
9.0 SOFTWARE INTERFACE .............................................. 42
9.1 SOFTWARE INTERFACE ..................................................................................................................................... 42
9.2 FORMAT FOR THE AT COMMANDS .................................................................................................................... 42
9.3 ENFORA AT COMMAND SET ............................................................................................................................. 42
10.0 SETUP AND INITIALIZATION ..................................... 43
10.1 GENERAL SETUP ............................................................................................................................................... 43
10.1.1 HyperTerminal Configuration for Enabler EDG0208 ............................................................................ 43
10.1.2 Initialization (AT Command Interface) ................................................................................................... 44
10.1.3 Initial Response to the AT Command ...................................................................................................... 45
10.1.4 Sending an Initialization String to the Enfora Enabler EDG0208 Module ............................................. 45
10.1.5 Setting Up the Communication Mode for the Enfora Enabler EDG0208 Module .................................. 45
10.1.6 Querying the Status of the Enfora Enabler EDG0208 Module ............................................................... 46
10.1.7 Setting Module Reporting Parameters for GSM and GPRS .................................................................... 46
10.2 GSM/SMS EXAMPLES ..................................................................................................................................... 46
10.2.1 Initialize the Enfora Enabler EDG0208 Module to Send and Receive SMS Text Messages .................... 46
10.2.2 Managing SMS Messages ........................................................................................................................ 46
10.2.3 Data Call Configuration ......................................................................................................................... 46
10.2.4 Voice Call Configuration ........................................................................................................................ 46
10.3 GPRS PACKET EXAMPLES ................................................................................................................................ 46
10.3.1 GPRS/EGPRS ATTACH and ACTIVATE ................................................................................................ 46
10.3.2 Windows PPP Setup ................................................................................................................................ 46
11.0 INTEGRATION AND TESTING .................................... 47
11.1 INTEGRATING THE ENFORA ENABLER EDG0208 MODULE ................................................................................ 47
11.2 APPENDIX A - LIMITED WARRANTY ...................................................................................................... 49
11.2.1 Scope ....................................................................................................................................................... 49
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11.2.2 Hardware ................................................................................................................................................ 49
11.2.3 Software .................................................................................................................................................. 49
11.2.4 Other Considerations .............................................................................................................................. 50
11.3 APPENDIX B - REGULATIONS AND COMPLIANCE ............................................................................................ 51
11.3.1 GCF/PTCRB Approval (Formerly FTA) ................................................................................................. 51
11.3.2 Electromagnetic Compatibility (EMC) and Safety Requirements ........................................................... 51
11.3.3 EMC/Safety Requirements for the USA ................................................................................................... 51
11.3.4 Human Exposure Compliance Statement ................................................................................................ 51
11.3.5 Compliance with FCC Regulations ......................................................................................................... 51
11.3.6 Unintentional Radiators, Part 15 ............................................................................................................ 52
11.3.7 Intentional Radiators, Part 22 & 24 ........................................................................................................ 52
11.3.8 Instructions to the Original Equipment Manufacturer (OEM) ................................................................ 53
11.3.9 OEM Responsibilities for All Products Containing the Enabler IIE module .......................................... 55
11.3.10 Specific OEM Responsibilities for Portable Products and Applications ............................................. 56
11.3.11 Specific OEM Responsibilities for Mobile Products and Applications ................................................ 56
11.3.12 Specific OEM Responsibilities for Fixed Products and Applications .................................................. 56
11.3.13 EMC/Safety Requirements for the Countries of the European Union (EU) ......................................... 56
11.3.14 EMC/Safety Requirements for Other Countries .................................................................................. 56
11.4 APPENDIX C - GLOSSARY AND ACRONYMS ................................................................................................... 57
11.5 APPENDIX D – TABLES AND FIGURES ........................................................................................................... 59
11.6 APPENDIX E - CONTACTING ENFORA ............................................................................................................. 60
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1.0 Safety Precautions
1.1 Important Safety Information
The following information applies to the devices described in this manual. Always observe all
standard and accepted safety precautions and guidelines when handling any electrical device.
Save this manual: it contains important safety information and operating instructions.
Do not expose the Enfora Enabler EDG0208 product to open flames.
Ensure that liquids do not spill into the devices.
Do not attempt to disassemble the product; doing so will void the warranty. With the exception
of the Subscriber Identification Module (SIM), this product does not contain consumerserviceable components.
2.0 Regulatory Compliance FCC
2.1 Integration Considerations and Installation Requirements
The Enabler IIE modem is designed for use in a variety of host units, "enabling" the host
platform to perform wireless data communications.
Operation is subject to the following two conditions: (1) this device may not cause
interference, and (2) this device must accept any interference, including interference
that may cause undesired operation of the device.
In order to use the Enabler IIE modem without additional FCC certification approvals,
the installation must meet the following conditions:
Maximum RF output power and antenna gain to meet Maximum Permissible Exposure
Requirements:
GSM850 mode: Maximum antenna gain is 6.5 dBi.
GSM1900 mode: Maximum antenna gain is 3.0 dBi.
If used in an application such as a handheld or body worn device with the antenna less than 20
cm (7.9 in.) from the human body when the device is operating, then the integrator is
responsible for passing additional "as installed" testing and the device will require it’s own FCC
ID and FCC testing.
If used in a "mobile" application where the antenna is normally separated at least 20 cm (7.9
in) from the human body during device operation, then an appropriate warning label must be
placed on the host unit adjacent to the antenna. The label should contain a statement such as
the following:
WARNING
RF exposure. Keep at least 20 cm
(7.9 in) separation distance from
the antenna and the human body.
Host unit user manuals and other documentation must also include appropriate caution and
warning statements and information.
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If the FCCID for the modem is not visible when installed in the host platform, then a
permanently attached or marked label must be displayed on the host unit referring to the
enclosed modem.
For example, the label should contain wording such as:
Any antenna used with the modem must be approved by the FCC or as a Class II Permissive
Change (including MPEL or SAR data as applicable). The "professional installation" provision
of FCC Part 15.203 does not apply.
The transmitter and antenna must not be co-located or operating in conjunction with any other
antenna or transmitter. Violation of this would allow a user to plug another transmitter in to the
product and potentially create an RF exposure condition.
2.2 Disclaimer
The information and instructions contained within this publication comply with all FCC, GCF,
PTCRB, R&TTE, IMEI and other applicable codes that are in effect at the time of publication.
Enfora disclaims all responsibility for any act or omissions, or for breach of law, code or regulation,
including local or state codes, performed by a third party.
Enfora strongly recommends that all installations, hookups, transmissions, etc., be performed by
persons who are experienced in the fields of radio frequency technologies. Enfora acknowledges
that the installation, setup and transmission guidelines contained within this publication are
guidelines, and that each installation may have variables outside of the guidelines contained
herein. Said variables must be taken into consideration when installing or using the product, and
Enfora shall not be responsible for installations or transmissions that fall outside of the parameters
set forth in this publication.
Contains GSM/GPRS/EDGE transmitter module
FCC ID: MIVEDG0208
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.
OR
Contains FCC ID: MIVEDG0208
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.
WARNING
The transmitter and antenna must not be collocated
or operating in conjunction with any
other antenna or transmitter. Failure to observe
this warning could produce an RF exposure
condition.
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Enfora shall not be liable for consequential or incidental damages, injury to any person or property,
anticipated or lost profits, loss of time, or other losses incurred by Customer or any third party in
connection with the installation of the Products or Customer's failure to comply with the information
and instructions contained herein.
The Enabler IIE platform is designed with features to
support a robust connection. There are instances
where the module performance is beyond the control
of the intended design. Integrated designs that require
24 by 7 operation must implement power control via an
external circuit or by implementing power management
as specified within this design guide.
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3.0 Manual Overview
This document describes the hardware interface of the Enabler EDG0208 GSM/GPRS OEM Modem. The
purpose of this document is to define the electrical, mechanical and software interfaces while providing
detailed technical information in order to streamline the process of hardware and system integration.
3.1 Reference Documents
3.1.1 Enfora Enabler EDG0208 Product Documentation
Manuals
EDG0208AT001 - Enfora Enabler IIE AT Command Set
Application Notes
GSM0000AN001 - Enabler-G PPP Configuration for Windows 98
GSM0000AN002 - Enabler-G PPP Configuration for Windows 2000
GSM0000AN003 - Enabler-G Data Circuit Switched Call Configuration and Use
GSM0000AN004 - Enabler-G SMS Configuration and Use
GSM0000AN005 - Enabler-G Automated Network Connection Configuration and Use
GSM0000AN006 - Enabler-G Module Status Query
GSM0000AN007 - Enabler-G Status Reporting
GSM0000AN008 - Enabler-G PPP Configuration for Windows XP
GSM0000AN013 - Enabler-G Sleep Mode Configuration and Use
GSM0000AN016 - How to Send SMS Messages to an E-Mail Address
Technical Notes
GSM0000TN001 - Enabler-G Firmware Upgrade
GSM0000TN002 - Enabler-G PPP Negotiation Sequence
GSM0000TN008 - Enabler Power Supply Requirements
GSM0000TN013 – Enabler III-G and IIE CMUX Description
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3.1.2 GSM Device Specifications: www.3gpp.org
3GPP TS 51010-1 (850, 900,1800,1900 MHz devices)
3.1.3 Federal Communications Commission (FCC)
Internet: http://www.fcc.gov/
FCC Rules, Part 24
47 CFR Subpart E--Broadband PCS
47 CFR § 24.52, sections 1.1307(b), 2.1091, and 2.1093
FCC Rules, Part 22 for GSM 850
FCC Rules, Part 15
FCC Rules, Part 2
Subpart J--Equipment Authorization Procedures
Section 2.925
3.1.4 FCC Office of Engineering and Technology (OET)
Internet: http://www.fcc.gov.oet/
Bulletin Number 65 "Evaluating Compliance with FCC Guidelines for Human Exposure
to Radio Frequency Electromagnetic Fields"
Supplement C "Additional Information for Evaluating Compliance of Mobile and
Portable Devices with FCC Limits for Exposure to Radio Frequency Emissions"
3.1.5 Industry Canada
RSS-132
RSS-133
ICES-003
3.1.6 Environmental Regulations
National Environmental Policy Act (NEPA) of 1969 (Part 1, Subpart 1)
3.1.7 Mechanical Specifications
ASTM D999
ASTM D775
IEC 68-2-27
Bellcore Gr-63-CORE
ETS 300 019-1-1 Class 1.2
ETS 300 019-1-2 Class 2.1
ETS 300 019-1-3 Class 3.1
3.1.8 RF and EMI Specifications
ETSI Standards
EN 61000-4-6
EN 61000-4-3
TS 51.010-1, Section 12.2
EN 55022 Class B
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4.0 Introduction
4.1 Product Overview
Enfora Enabler EDG0208 GSM/GPRS Radio modem is a compact, wireless OEM module that utilizes the
Global System for Mobile Communications (GSM), GPRS (General Packet Radio Services) and EDGE
international communications standard to provide two-way wireless capabilities via GSM services. The
Enfora Enabler EDG0208 module is a fully Type-approved GSM/GPRS/EDGE device, enabling applicationspecific, two-way communication and control. The Enfora Enabler EDG0208 module is available as a quad
band version.
The Enfora Enabler EDG0208 module is designed to be a drop in replacement for the Enabler II E EDG0108
module. It’s physical size, electrical specifications and physical connectors are identical to the EDG0108 for
a seamless transition.
4.2 Key Features of the GSM/GPRS OEM Module
The following table summarizes the main features of the Enfora Enabler EDG0208 Radio Module.
Interface Data input/output interface 60 position
Primary serial port V.24 protocol, 3 V levels
Voice Supports four vocoder modes: full-rate (FR), enhanced full-
rate (EFR), half-rate (HR) and adaptive multi-rate (AMR)
Antenna Interface ultra Miniature Coaxial Interconnect
Command protocol GSM AT command set
Subscriber Identification Module
(SIM)
Optional remote SIM Accessible via the 60-pin connector
Power Electrical power 3.3 to 4.5 Vdc
Peak currents and average
power dissipation
Radio Features Frequency bands EGSM 900, DCS 1800, PCS 1900 and GSM 850 capability.
Optional mini-SIM carrier and interface on board
Refer to the Operating Power table in the Technical
Specifications for peak currents and average power
dissipation for various modes of operation.
GSM/GPRS/EGPRS features
supported
Regulatory Agency approvals
GSM/GPRS/EGPR
S
Functionality
SIM 1.8 & 3 V Mini-Subscriber Identity Module (SIM) compatible
Mobile-originated and mobile-terminated SMS messages: up to 140 bytes or up to 160
GSM 7-bit ASCII characters.
Reception of Cell Broadcast Message
SMS Receipt acknowledgement
Circuit Switched Data (Transparent & Non-transparent up to 9.6 Kbps)
Voice (EFR, FR, HR, AMR)
Supports Unstructured Supplementary Service Data (USSD)
Multi-Slot Class 10 Supported (4Rx/2TX), (5 Slot Max)
PBCCH/PCCCH Supported
EGPRS Release 99
Provides for all GSM/GPRS/EGPRS authentication,
encryption, and frequency hopping algorithms. GPRS
Coding Schemes CS1-CS4 supported. Multi-Slot Class 10
(4RX/2TX, Max 5 Slots). EGPRS Coding Schemes MCS1-
MCS9 supported. Multi-Slot Class 10 (4RX/2TX, Max 5
Slots)
GCF Type Approval (Version 3.17.0)
PTCRB Type Approval (NAPRD 3.2.1)
FCC Certification
R&TTE
CE (European Community Certification)
IC (Industry Canada) Approval
Table 1 - Enabler EDG0208 Key Features
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4.3 Providing Multi-Band Operation
The Enfora Enabler EDG0208 module provides by default the appropriate multi-band operation, it is also
possible to select the operating frequency by AT Command. There are two modes of multi-band
environment available:
The GSMS850 / PCS1900 bands are available for use in North America and places where these
bands have been provisioned.
The GSM900 / DCS1800 MHz bands are available for use in Europe and the rest of the world.
4.4 Wireless Data Application Possibilities
A variety of applications can use the Enfora Enabler EDG0208 module for transmitting and receiving data
and voice, such as:
Automated Meter Reading (AMR)
Point of Sale Applications
E-mail and Internet access
Automated Vehicle Location (AVL)
Telematics
Telemetry
Wireless Security
Smart Phones
Telemedicine
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4.5 General design guidelines for utilizing Enfora GSM modules
The following guidelines are provided in an effort to allow Enabler IIE module users to successfully
implement their PCB layout to obtain the best performance. This includes the lowest possible EMI
emissions, maximum thermal conduction, mechanical integrity, and voice quality. The Enabler IIE
module is a very compact, high performance design, yet it is easy to interface into the final product. In
order to realize its full potential, designers should pay close attention to ground structures, the routing of
RF and Digital traces, and the size of the power supply lines.
These design tips are strictly guidelines and are not
meant to be a complete list of items that guarantee
actual performance. Each application is different and
may require variation from these guidelines, however,
care should be given to utilize these sound engineering
principles whenever possible.
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4.6 Advanced tips for an RF friendly layout
Ground Plane
To ensure the lowest possible EMI emissions and maximum thermal conductivity, it is
recommended that all metal tabs on the GSM module shield must be soldered down onto a
continuous ground plane that runs under the entire module. Ample ground vias should be
provided around the metal tabs to create a low impedance ground. It is recommended to
minimize the number of I/O and power traces and vias under the GSM module to allow for as
much ground plane as possible. If the integrated unit includes more than one board, the design
must guarantee a good RF ground connection between the boards in order to make sure the
ground planes are at the same RF potential. An example of a good ground structure and pad
layout is shown below in Figure 1.
Figure 1 - Example of good ground plane for GSM modules
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Thermal Relief
Because the ground plane acts as a large heat sink, it can affect the solderability of
components. A common method to reduce this effect is to use thermal relief around the pad in
question. However, great care must be taken when using thermal relief for high current or high
frequency applications
For example, a large thermal relief like the one shown in Figure 2 can serve the purpose for
general applications such as low current, low speed data lines, DC connections and audio
frequency applications. Such thermal relief structures should be avoided for applications
where high current and/or high frequency is involved, such as those using the Enabler Module.
Depending on the frequency of operation, the long narrow thermal relief traces between the
pad and the ground plane act like an RF choke. These RF chokes become higher impedance
at harmonics of the fundamental frequency making it problematic for high frequency
suppression. This can make it difficult to pass type approval testing.
POOR RF thermal relief
Figure 2 - Example of a POOR RF Thermal Relief
If thermal relief is necessary, it is recommended that you use short, fat traces similar to those
shown in Figure 3. This will still provide a solderable connection, while providing a better RF
connection. Making them shorter also allows for a more continuous ground plane due to less
copper being removed from the area. It is also recommended to have ground vias around all
thermal relief of critical ground pins such as the five Enabler shield tabs.
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Figure 3 - Example of a GOOD RF Thermal Relief
Antenna and RF Signal Trace
The PCB trace that feeds the RF output port must be designed for a 50 ohm characteristic
impedance, coplanar, or routed into internal layers to keep the top layer continuous around
and underneath the Enabler module. Ample ground vias should be provided around the RF
contacts, the RF trace and launch pad. If possible, keep I/O and power traces away from the
RF port. This includes traces running parallel or orthogonal to it. Thermal relief should not be
used on the antenna output port ground pads. The designer must pay close attention to the
size of the pad and thickness of the dielectric beneath the signal pad and trace. Most PCB
manufacturers can adjust the trace width to maintain 50 ohms impedance if the traces are
identified and instructions are included on the FAB drawing. This service is typically provided
at no or minimal additional cost.
For minimum RF emissions due to the fundamental frequency of operation, the Enabler
module works best with an antenna load that has a VSWR of 1.5:1 or better. The antenna
should not have gain at the harmonic frequencies, otherwise, the conducted harmonics could
get amplified to a point where the product no longer passes type approval. However, for
applications where antenna quality is less than ideal, it is recommended to have a low pass
filter (Pi structure with N=3) in the RF path to the antenna. This is a secondary plan should
there be a need to lower harmonic levels at frequencies above the PCS band. The pad
structure may also be used to match the antenna load impedance, if required. If it is not
needed, a capacitor of low reactance may be used to bridge the Pi structure.
The RF cable going between the Enable module and the antenna is very lossy, therefore, the
length of this cable should be kept as short a possible.
If multiple antennas are used in their design, care should be taken during placement selection
to minimize the coupling between the GSM antenna and the other antennas.
GOOD RF thermal relief
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Vbat Input
The Enabler Vbat input can have a relative high current draw that can fluctuate rapidly,
especially when transmitting at max power and burst mode. The Vbat interface must be
designed to provide the required instantaneous voltage and current with minimal voltage
droop. This includes both sufficient bulk decoupling capacitance as well as adequate layout
provisions.
When laying out the connections to the Enabler interface connector, it is tempting to use traces
of the same width as the connector pins. However, this is a very compact connector and
traces of that width will not have sufficient copper. Similar to the discussion on thermal relief,
the use of narrow traces to connect the Vbat pins to the source voltage can act like a high
impedance and cause a significant voltage droop when higher currents are required as shown
in Figure 4.
Figure 4 - Example of Vbat Voltage Droop
If the Vbat drops too low, the Enabler modules will reset. To minimize the trace loss, it is
suggested to use a larger trace that spans several pins as shown in Figure 5. Any concern
about solderability can be mitigated by using solder mask with cutouts for the individual pins as
shown by the blue lines in the figure. The layout should provide sufficient trace width over the
entire trace from the Enable modules all the way to the source of the Vbat voltage. Any
transitions between layers for this trace should utilize multiple vias.
Since even the best layout will have some impedance from the source to the Enabler module,
sufficient bulk decoupling capacitance is required at the Vbat input to the Enabler module. It is
suggested to use at least two 1000 uF, low ESR, tantalum capacitors located very close to the
Enabler interface connector Vbat pins. Any thermal relief used on these capacitors should
comply with the information given above in order to provide the lowest impedance possible.
The grounding of these capacitors is critical. Therefore, it should be a low impedance and
should utilize multiple vias to the internal ground plane close to the capacitor as well.
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Figure 5 - Example of GOOD Vbat layout
4.7 Audio Reference Design
The audio quality is very dependent on the circuit design and layout. As an aid to
obtaining good audio quality, a reference design has been included below. It has been
proven to provide good performance on the SDK module.
Audio Schematics
Vbat trace
EDG0208IG001 Page 13 Rev. 1.03 –4/19/07
Integration Guide
Draft
Figure 6 - Audio Reference Design Schematic
Audio Layout
Layout plots for the audio section of the SDK are available upon request.
EDG0208IG001 Page 14 Rev. 1.03 –4/19/07
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Draft
5.0 Technical Specifications
5.1 Enabler EDG0208 Module Block Diagram
PWR
Ser. Intfc.
Audio
SIM
GPIO
Analog
Baseband/
Power
Mgmt
Digital
Baseband/
CPU
Figure 7 Enabler EDG0208 Module Block Diagram
Analog BB
Interface
SRAM/
Flash
Memory
RF
VCO
RX Intfc. RF
Antenna
Intfc.
PA
EDG0208IG001 Page 15 Rev. 1.03 –4/19/07
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