Multitech MTMMC-G-F1 Instruction Manual

GSM/GPRS
Embedded Data/Fax/Voice Wireless Modem
MTMMC-G-F1
MTMMC-G-F2
Developer’s Guide

Wireless ModemModule MTMMC-G-F1 and MTMMC-G-F2 Developer’s Guide 2
ModemModule Developer’s Guide
MTMMC-G-F1 and MTMMC-G-F2
PN S000295A, Version A
07/15/03
Copyright
This publication may not be reproduced, in whole or in part, without prior expressed written permission from
Multi-Tech Systems, Inc. All rights reserved.
Copyright © 2003, by Multi-Tech Systems, Inc.
Multi-Tech Systems, Inc. makes no representations or warranties with respect to the contents hereof and
specifically disclaims any implied warranties of merchantability or fitness for any particular purpose. Furthermore,
Multi-Tech Systems, Inc. reserves the right to revise this publication and to make changes from time to time in
the content hereof without obligation of Multi-Tech Systems, Inc. to notify any person or organization of such
revisions or changes.
Revisions
Revision Level Date Description
A07/15/03 First release.
Patents
This device is covered by patent number 5,673,268.
Trademarks
Trademarks of Multi-Tech Systems, Inc. are ModemModule and the Multi-Tech logo.
MNP and Microcom Network Protocol are registered trademarks of Microcom, Inc.
Microsoft, Windows, Windows 95, and Windows NT are either registered trademarks or trademarks of Microsoft
Corporation in the United States and/or other countries.
World Headquarters
Multi-Tech Systems, Inc.
2205 Woodale Drive
Mounds View, Minnesota 55112
Phone: [phone] or 800-328-9717
Fax: [phone]
Technical Support
Country By Email By Phone
France: [e-mail] (33) 1-64 61 09 81
India: [e-mail] 91 (124) 6340778
U.K.: [e-mail] (44) 118 959 7774
U.S. and Canada: [e-mail] [phone]
Rest of the World: [e-mail] [phone]
Internet Address: http://www.multitech.com

Wireless ModemModule MTMMC-G-F1 and MTMMC-G-F2 Developer’s Guide 3
Table of Contents
CHAPTER 1 – PRODUCT DESCRIPTION AND SPECIFICATIONS ................................................................5
INTRODUCTION ...........................................................................................................................................................5
Scope of the Developer Guide ................................................................................................................................5
GENERAL CHARACTERISTICS......................................................................................................................................6
General...................................................................................................................................................................6
Electrical ................................................................................................................................................................6
Mechanical .............................................................................................................................................................6
FEATURE DETAILS ......................................................................................................................................................6
Telephony ...............................................................................................................................................................6
Short Message Service (GSM and GPRS mode).....................................................................................................6
GSM Circuit Data Features ...................................................................................................................................7
GPRS Packet Data Features ..................................................................................................................................7
GSM Supplementary Services.................................................................................................................................7
Other Features .......................................................................................................................................................7
Interfaces................................................................................................................................................................7
FEATURE DESCRIPTIONS .............................................................................................................................................8
APPLICATIONS ............................................................................................................................................................9
MECHANICAL DESIGN OVERVIEW ............................................................................................................................10
CHAPTER 2 – MECHANICAL SPECIFICATIONS............................................................................................11
MECHANICAL DIMENSIONS.......................................................................................................................................11
CLIMATIC AND MECHANICAL ENVIRONMENT TESTING COMPLIANCE ......................................................................12
CHAPTER 3 – ELECTRICAL CHARACTERISTICS.........................................................................................13
INTRODUCTION .........................................................................................................................................................13
50-PIN CONNECTOR INTERFACES..............................................................................................................................14
50-Pin Connector Description..............................................................................................................................14
Power Supply........................................................................................................................................................17
Serial Link ............................................................................................................................................................19
ON / ~OFF Interface ............................................................................................................................................20
BOOT ...................................................................................................................................................................22
Reset Signal (~RST)..............................................................................................................................................22
Flashing LED .......................................................................................................................................................23
General Purpose Input/Output .............................................................................................................................24
Analog to Digital Converter.................................................................................................................................24
Audio Interface .....................................................................................................................................................25
SIM interface ........................................................................................................................................................29
SPI Bus .................................................................................................................................................................31
Keypad Interface ..................................................................................................................................................31
CHAPTER 4 – INTERFACES .................................................................................................................................32
FLASHING LED.........................................................................................................................................................32
SIM INTERFACE........................................................................................................................................................32
RF INTERFACE ..........................................................................................................................................................33
RF Connector .......................................................................................................................................................33
RF Performances..................................................................................................................................................33
DTE/DCE INTERFACE RATES...................................................................................................................................33
CHAPTER 5 – TEST BOARD .................................................................................................................................34
SERIAL TEST/DEMO BOARD COMPONENTS...............................................................................................................34
SERIAL TEST/DEMO BOARD BLOCK DIAGRAM .........................................................................................................35
SIM Schematic (5V)..............................................................................................................................................36
CHAPTER 6 – APPLICATION CONSIDERATIONS..........................................................................................37

Wireless ModemModule MTMMC-G-F1 and MTMMC-G-F2 Developer’s Guide 4
GENERAL GUIDELINES FOR THE USE OF THE MODEMMODULE.................................................................................37
Hardware and RF.................................................................................................................................................37
The Antenna..........................................................................................................................................................37
Firmware Upgrade...............................................................................................................................................37
Initial Configuration Using Mobile PhoneTools..................................................................................................37
Getting Started .....................................................................................................................................................38
REFERENCE DOCUMENTS..........................................................................................................................................39
RELATED MANUALS .................................................................................................................................................39
ADDITIONAL INFORMATION......................................................................................................................................40
APPENDIX A – SAFETY PRECAUTIONS & REGULATORY STANDARDS COMPLIANCE....................41
SAFETY PRECAUTIONS..............................................................................................................................................41
RF Safety ..............................................................................................................................................................41
General Safety ......................................................................................................................................................42
Safety Standards ...................................................................................................................................................42
RF Exposures .......................................................................................................................................................43
Instructions to OEMs............................................................................................................................................43
REGULATORY STANDARDS COMPLIANCE .................................................................................................................44
GSM compliance ..................................................................................................................................................44
FTA Compliance...................................................................................................................................................45
APPENDIX B – SOURCING GUIDE FOR CONNECTORS AND PERIPHERAL DEVICES........................46
WHERE TO FIND SMD CONNECTORS........................................................................................................................46
GSM ANTENNA........................................................................................................................................................47
SIM CARD HOLDER..................................................................................................................................................47
APPENDIX C – AT COMMAND LIST ..................................................................................................................48
APPENDIX D – ACRONYMS AND ABBREVIATIONS .....................................................................................53
INDEX ........................................................................................................................................................................54
LIST OF TABLES ...................................................................................................................................................57

Chapter 1 – Product Description & Specification
Wireless ModemModule MTMMC-G-F1 and MTMMC-G-F2 Developer’s Guide 5
Chapter 1 – Product Description and Specifications
Introduction
ModemModule GSM/GPRS integrated wireless modems provide a quick and easy way to insert GSM and GPRS
functionality into systems and terminals. Available in dual-band configurations, this fully type approved integrated
modem constitutes a self-contained, fully integrated implementation of the GSM/GPRS standard. Thanks to
standard interfaces, it can be integrated into any system. It is ready for voice, SMS, data and fax. ModemModule
GSM/GPRS is a product with a single connector, which puts together all interface signals in order to facilitate its
integration. It has an integrated SIM connector as well as a standard RF connector type MMCX. For system
integrators, ModemModule GSM/GPRS is the fast track to the wireless world.
Figure 1-1: MultiTech’s Wireless ModemModule GSM/GPRS
Product Description Region
MTMMC-G-F1 GSM/GPRS Class 10, 900/1800 MHz Global
MTMMC-G-F2 GSM/GPRS Class 10, 850/1900 MHz Global
The MTMMC-G-F1 and MTMMC-G-F2 ModemModules are used to integrate wIreless data and fax
communications in numerous embedded applications.
Scope of the Developer Guide
This document describes the hardware interface and the technical specifications of the ModemModule
GSM/GPRS wireless modems. The integrated modem is referred to as ModemModule GSM/GPRS according to
the GSM/GPRS 900 standard, the GSM/GPRS 1800 standard and the GSM/GPRS 1900 standard. This product
is based on a Dual Band RF module:every integrated modem referenced ModemModule GSM/GPRS-
G900/1800 includes a GSM 900/1800 MHz module and every integrated modem referenced ModemModule
GSM/GPRS-G850/1900 includes a GSM 850/1900 MHz module. These two dual-band modems have the same
specifications unless otherwise specified.

Chapter 1 – Product Description & Specification
Wireless ModemModule MTMMC-G-F1 and MTMMC-G-F2 Developer’s Guide 6
General Characteristics
General
·GPRS Class 10
·Dual Band GSM/GPRS modem E-GSM 900/1800 or GSM 850/1900
·2W at 850MHz
·1W at 1800/1900 MHz
·GSM Class 1 and Class 2 Group 3 FAX
·Small size and low power consumption
·Voice and Short Message Services (SMS)
·Fax and data transmission without extra hardware
·Serial interface supports DTE speeds up to 115.2K
·MMCX connector and SIM socket
·14.4K GSM circuit-switched data
·Tricodec (FR/EFR/HR)
·Internal 3V SIM interface
·Easy remote control by AT commands for dedicated applications
·Fully Type Approved according to GSM Phase 2+ specifications
·Board-to-board or board-to-cable mounting
·Fully shielded and ready-to-use
Electrical
·Power supply: 5 VDC +/- 5% 1A
Mechanical
·Absolute maximum dimension: 46 x 64 x 12 mm
·Weight: 79 g
·Casing: Complete shielding-stainless steel/zinc
·Mounting: 4 screw holes
·Operating temperature range: -30°C to + 60°C
·Storage temperature: -35°C to +85°C
Feature Details
Telephony
·Telephony (TCH/FS) & Emergency calls
·Full Rate, Enhanced Full Rate and Half Rate
·Dual Tone Multi Frequency function (DTMF)
Short Message Service (GSM and GPRS mode)
·Text and PDU
·Point to point MT & MO
·SMS Cell Broadcast

Chapter 1 – Product Description & Specification
Wireless ModemModule MTMMC-G-F1 and MTMMC-G-F2 Developer’s Guide 7
GSM Circuit Data Features
·Data circuit asynchronous, transparent and non transparent up to 14,400
·bits/s
·Automatic fax group 3 (Class 1 & 2)
·Alternate speech and fax
·MNP2, V.42bis data compression
GPRS Packet Data Features
·GPRS Class 10
·Coding Schemes: C1S1 to CS4
GSM Supplementary Services
·Call Forwarding
·Call Barring
·Multiparty
·Call Waiting and Call Hold
·Calling Line Identity
·Advice of Charge
·USSD
·Closed User Group
·Explicit Call Transfer
Other Features
·ME+SIM phone book management
·Fixed Dialing Number
·SIM Toolkit Class 2
·SIM, network and service provider locks
·Real Time Clock
·Alarm management
·Software upgrade through Xmodem protocol
·UCS2 character set management
Interfaces
Single antenna interface
Internal SIM interface: 3V only
External SIM interface: 3V or 5V
For Data Operation:
Serial link
Remote control by AT commands (GSM 07.07 and 07.05)
Baud rate from 300 to 115,200 bits/s
From 300 up to 38400 bits/s with autobauding
The integrated modem has a sole 50-pin connector, which gathers all the interface signals in order to facilitate its
integration. It has an integrated SIM card holder as well as a standard RF connector type MMCX. The concept
of the integrated modem has been defined to integrate on a sole device:
·a single connector has been used that is standard and easy to find (it is supplied worldwide);
this connector includes all of the modem’s analog and digital connections
·One standard easy to find RF connector. See RF connector section in Chapter 3: Electrical
Characteristics;
·One SIM card holder. See SIM section in Chapter 3: Electrical Characteristics.

Chapter 1 – Product Description & Specification
Wireless ModemModule MTMMC-G-F1 and MTMMC-G-F2 Developer’s Guide 8
Feature Descriptions
Integration Reduces Space, Power and Cost. The ModemModule GSM/GPRS integrates the
controller, RF transceiver, and antenna interface in one compact unit. This integration requires low power,
occupies very little space, and provides an overall reduction in costs.
Reduces Development Time. The ModemModule GSM/GPRS can make your existing and next
generation device, machine, or system, communication-ready without requiring significant hardware
changes to its design. It actually provides faster time-to-market because it relieves the burden and expense
of obtaining network and RF approvals. This complete, ready-to-integrate wireless module allows you to
enhance your product while you focus on developing its core features.
Voice Features. The ModemModule GSM/GPRS provides telephony and Dual Tone Multi Frequency (DTMF)
functionality. It also allows for emergency calls as well as full rate, enhanced Full Rate and Half Rate
(FR/EFR/HR).
Short Message Services. The ModemModule GSM/ GPRS offers SMS features such as text and PDU, point-
to-point (MT/MO) and cell broadcast.
Compatible Supplementary Services. The ModemModule GSM/GPRS is compatible with supplementary
services such as call forwarding, call barring, multiparty, call waiting and call hold, calling line identification,
advice of charge, USSD, closed user group and explicit call transfer.
Management Features. The ModemModule GSM/ GPRS provides advanced management features including
phone book management, fixed dialing number, real time clock and alarm management.
Industry-standard Modem Commands. The ModemModule GSM/GPRS provides industry-standard
AT-style commands for ease of integration into your existing software application.
ModemModule Pin-Out. The ModemModule GSM/ GPRS interfaces easily with existing products
through a standard serial communication channel. The complete on-board RF transceiver interfaces with
an antenna for direct connection to wireless SMS, circuit-switched dial-up, or packet data networks. The
ModemModule is a Data Terminal Equipment (DTE) device with serial asynchronous protocol support. The
serial DTE channel is capable of transfer speeds to 115.2K bps and can be interfaced directly to a UART
or microcontroller. It can be board-to-board or board-to-cable mounted.
Network and RF Approved. The ModemModule GSM/ GPRS has been tested and certified with
wireless telecom network providers worldwide. In addition, it has successfully completed worldwide
compliance
Developer’s Kit. The ModemModule GSM/GPRS Developer’s Kit allows you to plug in the
ModemModule and use it for testing, programming and resolving application issues.

Chapter 1 – Product Description & Specification
Wireless ModemModule MTMMC-G-F1 and MTMMC-G-F2 Developer’s Guide 9
Applications
With circuit switched data rates up to 14.4K bps, the MultiModem GSM/GPRS is targeted at applications that
periodically need to send or receive data over a wireless network. It is an ideal device for:
Appliances Remote Diagnostics
ATM Terminals Remote Metering
Automotive Security Systems
Data Collection Vending/Gaming
Machines
Gas Pumps Other devices requiring
wireless connectivity.
Industrial and Medical
Remote Monitoring
Systems
Note: The Wireless
MultiModem must be
mounted with at least 8
inches (20 cm) of clearance
from the human body.

Chapter 1 – Product Description & Specification
Wireless ModemModule MTMMC-G-F1 and MTMMC-G-F2 Developer’s Guide 10
Mechanical Design Overview
The ModemModule is encased as shown in the figure below. It includes a RF module, a 50-pin connector, a SIM
holder and a RF connector.
Interface Connector
Figure 1-2: Mechanical Description A
Holes for Mounting
Screws (4)
Hole dia. = 0.087”
SIM Reader
Antenna Connector
(MMCX type)
SIM ejection button
Figure 1-3: Mechanical Description B
Four screw holes allow the ModemModule to be fixed on the mother PCB. The ModemModule can be mounted
indifferently on both sides (top or bottom). For further details see Chapter 2: Mechanical Specifications.

Chapter 2 – Mechanical Specifications
Wireless ModemModule MTMMC-G-F1 and MTMMC-G-F2 Developer’s Guide 11
Chapter 2 – Mechanical Specifications
Mechanical Dimensions
Figure 2-1: ModemModule Dimensions

Chapter 2 – Mechanical Specifications
Wireless ModemModule MTMMC-G-F1 and MTMMC-G-F2 Developer’s Guide 12
Climatic and Mechanical Environment Testing Compliance
Table 2-1 : Climatic and Mechanical Environment Testing Compliance
G900/G1800 Environmental
Type of Test Standards Storage
Class 1.2
Transportation
Class 2.3
Operating (Port Use)
Class 7.3
Cold IEC 68-2.1
Ab test
-25OC; 72 hours -40OC; 72 hours -20OC (GSM); 16 hours
-10OC (DCS) 16 hours
Dry Heat IEC 68-2.2
Bb test
+70OC; 72 hours +70OC; 72 hours +55OC; 16 hours
Change of
Temperature
IEC 68-2.14;
Na/Nb test -40O/+30O C; 5 cycles
t1 = 3 hours
-20O/+30OC(GSM); 3 cycles
-10O/+30OC(DCS); 3 cycles
t1 = 3 hours
Damp Heat
Cyclic
IEC 68-2.30;
Db test +30OC; 2 cycles
90% - 100% RH
variant 1
+40OC; 2 cycles
90% - 100% RH
variant 1
+40OC; 2 cycles
90% - 100% RH
variant 1
Damp Heat IEC 68-2.56
Cb test
+30OC; 4 days +40OC; 4 days +40OC; 4 days
Sinusoidal
Vibration
IEC 68-2.6
Fc test
5 - 62 Hz : 5 mm/s
62 – 200 Hz: 2 m/s2
3 x 5 sweep cycles
Random
Vibration
IEC 68-3.36
Fdb test
5 – 20 Hz: 0.96 m2/s3
20 – 500 Hz: -3 dB/ oct
3 x 10 min
10 – 12 Hz: 0.96 m2/s3
12 – 150 Hz: -3 dB/ oct
3 x 30 min

Chapter 3 – Electrical Characteristics
Wireless ModemModule MTMMC-G-F1 and MTMMC-G-F2 Developer’s Guide 13
Chapter 3 – Electrical Characteristics
Introduction
This chapter describes the ModemModule’s electrical interfaces. These are:
·interfaces on the 50-pin general purpose connector (power and data/signaling)
·RF interface
·SIM interface

Chapter 3 – Electrical Characteristics
Wireless ModemModule MTMMC-G-F1 and MTMMC-G-F2 Developer’s Guide 14
50-Pin Connector Interfaces
50-Pin Connector Description
Table 3-1. 50-pin Connector Description
Pin # Name I/O I/O Type Description Comment
1 GND GROUND High current
2 GND GROUND High current
3 +5V Supply High current
4 +5V Supply High current
5 CT109/DCD O CMOS/2X Data Carrier Detect
6 GND GROUND High current
7 GPI04 I/O CMOS/2X General Purpose I/O
8 SPK2N O Analog Speaker 2 negative output
9 CT125/RI O CMOS/2X Ring Indicator
10 SPK2P O Analog Speaker 2 positive output
11 Flashing LED I/O CMOS/2X Working mode indication
LED
Driven by
module
12 SPK1P O Analog Speaker 1 positive output
13 CT106/CTS O 1X Clear to Send
14 SPK1N O Analog Speaker 1 negative output
15 ON/~OFF I Power ON/OFF control ON = Vcc
16 MIC2P I Analog Microphone 2 positive
input
17 AUXV0 I Analog Auxiliary ADC input
18 MIC2N I Analog Microphone 2 negative
input
19 ~RST I Reset active low Open Collector
20 MIC1P I Analog Microphone 1 positive
input
21 GND I Ground
22 MIC1N I Analog Microphone 1 negative
input
23 BOOT I BOOT Open Collector
24 GND GROUND High Current
25 CT103/TX I Transmit Data Pull up with
100K-ohm
when not used

Chapter 3 – Electrical Characteristics
Wireless ModemModule MTMMC-G-F1 and MTMMC-G-F2 Developer’s Guide 15
Table 3-1. 50-Pin Connector Description (Continued)
Pin # Name I/O I/O Type Description Comment
26 GPIO0 I/O CMOS/2X General Purpose I/O
27 CT107/DSR O 1X Data Set Ready
28 CT104/RX O 1X Receive Data
29 CT108-2/DTR I Data Terminal Ready Pull up with
100K-ohm
when not used
30 CT105/RTS I Request to Send Pull up with
100K-ohm
when not used
31 COL3 I/O 1X Keypad column
32 COL4 I/O 1X Keypad column
33 COL1 I/O 1X Keypad column
34 COL2 I/O 1X Keypad column
35 ROW4 I/O 1X Keypad row
36 COL0 I/O 1X Keypad column
37 ROW2 I/O 1X Keypad row
38 ROW3 I/O 1X Keypad row
39 ROW0 I/O 1X Keypad row
40 ROW1 I/O 1X Keypad row
41 NC Not Connected
42 SPI_EN O 1X SPI enable
43 SPI_IO I/O 1X I2C Data or SPI Data
44 SPI_CLK O 2X I2C Clock or SPI Clock
45 SIMCLK O 2X Clock for SIM interface 3V mode
46 SIMRST O 2X Reset for SIM interface 3V mode
47 SIMVCC O SIM card supply 3V mode
6mA max.
48 SIMPRES I SIM card detect Connected to
SIM connector
pin 8. Pin 4 of
SIM connector
must be pulled
down to GND
with 1 K-Ohm*
49 SIMDATA I/O 3X I/O for SIM interface 3V mode
50 GPO0 General purpose I/O
* See SIM socket diagram in SIM interface section
** GPO0 is a general purpose output for selection of external SIM, 3V or 5V.

Chapter 3 – Electrical Characteristics
Wireless ModemModule MTMMC-G-F1 and MTMMC-G-F2 Developer’s Guide 16
Table 3-2. Operating Conditions
Parameter I/O Type Min Max Condition
Vinput low CMOS -0.5V 0.8V
Vinput high CMOS 2.1V 3.0V
1X 0.2V IOL = -1mA
2X 0.2V IOL = -2mA
Voutput low
3X 0.2V IOL = -3mA
1X 2.6V IOH = 1mA
2X 2.6V IOH = 2mA
Voutput high
3X 2.6V IOH = 3mA
Figure 3-1: 50-Pin Connector

Chapter 3 – Electrical Characteristics
Wireless ModemModule MTMMC-G-F1 and MTMMC-G-F2 Developer’s Guide 17
50 49
21
Figure 3-2: Pin Numbering – Bottom View
Power Supply
The main power supply is provided through a double connection. These connections are respectively pins 3 and
4 for the +5V and the pins 1 and 2 for the ground (GND). The pins 6, 21, and 24 are also ground connection in
order to produce a proper ground plane.
A 5V +/-5% - 1A power is strictly required to supply the modem. Otherwise, serious dysfunctions may appear.
However, the modem does not have to constantly deliver 1A current at 5V on this power supply.
This power supply is internally regulated to a nominal value VBATT.
Table 3-3: Power Supply Pin Description
Pin Number Name Description Comment
1 GND Ground High Current
2 GND Ground High Current
3 +5V Ground High Current
4 +5V Ground High Current
6 GND Ground High Current
21 GND Ground High Current
24 GND Ground High Current
Table 3-4: Power Consumption in EGSM-only mode @25 degrees C
Conditions INOM IMAX
+5V During TX bursts @2W 810 mA 1 A
+5V Average @ 2W 310 mA 370 mA
+5V Average @ ).5W 185 mA 200 mA
+5V Average idle mode 22 mA 25 mA

Chapter 3 – Electrical Characteristics
Wireless ModemModule MTMMC-G-F1 and MTMMC-G-F2 Developer’s Guide 18
Table 3-5: Power Consumption in GSM-only 1800 & 1900 MHz modes @25 degrees C
Conditions INOM IMAX
+5V During TX bursts @1W 635 mA 800 mA
+5V Average @1W 260 mA 280 mA
+5V Average @ 0.25W 150 mA 170 mA
+5V Average idle mode 20 mA 22 mA
Table 3-6: Power Consumption in EGSM/GPRS 900 MHz and GSM/GRPS 850 MHz Mode
Class 10
Conditions INOM IMAX
+5V During TX bursts @PcI5 1.7 A peak 2.0 A peak
+5V During RX bursts 75 mA peak 80 mA peak
+5V Average 1Rx/1Tx @PcI5 270 mA 320 mA
+5V Average 1Rx/1Tx@PcI8 180 mA 200 mA
+5V Average idle mode 100 mA 300 mA
+5V Average GPRS CI 10
(3Rx/2Tx) @PcI5
540 mA 640 mA
+5V Average GPRS CI 10
(3Rx/2Tx) @PcI8
360 mA 400 ma
+5V Average Idle mode 2,2 mA 3 Ma
Power Control Level: PcI5=2W typ.; PcI8=0,5W typ.
Table 3-7: Power Consumption in GSM/GRPS 1800 MHz and GSM/GRPS 1900 MHz
Class 10
Conditions INOM IMAX
+5V During TX bursts @PcI0 1.3 A peak 1.7 A peak
+5V During RX bursts 75 mA peak 80 mA peak
+5V Average 1Rx/1Tx @PcI5 240 mA 270 mA
+5V Average 1Rx/1Tx@PcI8 150 mA 180 mA
+5V Average idle mode 100 mA 300 mA
+5V Average GPRS CI 10
(3Rx/2Tx) @PcI5
480 mA 540 mA
+5V Average GPRS CI 10
(3Rx/2Tx) @PcI8
300 mA 360 Ma
+5V Average Idle mode 2,2 mA 3 Ma
Power Control Level: PcI0=1W typ; PcI3=0,25W typ

Chapter 3 – Electrical Characteristics
Wireless ModemModule MTMMC-G-F1 and MTMMC-G-F2 Developer’s Guide 19
Serial Link
A serial link interface is available complying with V24 protocol signaling but not with V28 (electrical interface) due
to a 2.8 Volts interface. TX, RTS and DTR can be either 5V or 3V.
The signals are Tx data (CT103/TX), Rx data (CT104/RX), Request To Send (CT105/RTS), Clear To Send
(CT106/CTS), Data Terminal Ready (CT108-2/DTR) and Data Set Ready (CT107/DSR).
The set of RS232 signals can be required for GSM DATA services application. The 2 additional signals are Data
Carrier Detect (CT109/DCD) and Ring Indicator (CT125/RI).
Table 3-8: Serial Link Pin Description
Signal Pin Number I/O I/O Type* Description
CT103 / TX 25 I CMOS Transmit serial data
CT104 / RX 28 O 1X Receive serial data
CT105 / RTS 30 I CMOS Ready to send
CT106 / CTS 13 O 1X Clear to send
CT107 / DSR 27 O 1X Data set ready
CT108-2 / DTR 29 I CMOS Data terminal ready
CT109 / DCD 5 O CMOS / 2X Data carrier detect
CT125 / RI 9 O CMOS / 2X Ring indicator
* See “Table 3-2: Operating Conditions” in section on the 50-pin Connector Description.

Chapter 3 – Electrical Characteristics
Wireless ModemModule MTMMC-G-F1 and MTMMC-G-F2 Developer’s Guide 20
Modem Te rm in a lLevel Shifter
Vcc
RI
DCD
RX
CTS
DSR
DTR
TX
RTS
Vcc
28
25
1
3
24
23
22
19
17
16
21
20
18
13
C1+
C1-
C2+
T1IN
T2IN
T3IN
T4IN
T5IN
R1OUTB
R2OUT
R3OUT
R4OUT
ON
C2-
T1OUT
T2OUT
T3OUT
T4OUT
T5OUT
R1IN
R2IN
R3IN
ERROR
OFF
27
2
26
4
5
6
7
10
12
8
9
11
15
14
S_RI
S_DCD
S_RX
S_CTS
S_DSR
S_DTR
S_TX
S_RTS
Vcc
Vcc
GND
Vcc
GND
MAX 3238
*This appli cation n ote i s valid for Vcc> 3.0 Volt (se e MAX 32 38 specification s)
Auto shut down mo de is no t used in th is examp le.
Figure 3-3: Level Shifter Application Diagram for Serial Link
ON / ~OFF Interface
This input is used to switch ON or OFF the ModemModule. A high level signal has to be provided on the
ON/~OFF pin to switch on the modem. The level of the voltage of this signal has to be maintained to VCC during
a minimum time of 1 second. When powered off, the shutdown current is roughly 60 microAmperes.
Table 3-9: ON / OFF Pin Description
Signal Pin Number I/O I/O Type* Description
ON / ~OFF 15 I CMOS Module Power ON/OFF