Quectel M50 Supplement

M50Hardware Design
M50_HD_V2.0 - 1 -
M50
Quectel Cellular Engine
Hardware Design
M50_HD_V2.0

M50Hardware Design
M50_HD_V2.0 - 2 -
Document Title M50 Hardware Design
Revision 2.0
Date 2012-06-26
Status Released
Document Control ID M50_HD_V2.0
General Notes
Quectel offers this information as a service to its customers, to support application and
engineering efforts that use the products designed by Quectel. The information provided is
based upon requirements specifically provided for customers of Quectel. Quectel has not
undertaken any independent search for additional information, relevant to any information
that may be in the customer’s possession. Furthermore, system validation of this product
designed by Quectel within a larger electronic system remains the responsibility of the
customer or the customer’s system integrator. All specifications supplied herein are subject to
change.
Copyright
This document contains proprietary technical information of Quectel Co., Ltd. Copying this
document, distribution to others, and communication of the contents thereof, are forbidden
without permission. Offenders are liable to the payment of damages. All rights are reserved in
the event of a patent grant or registration of a utility model or design. All specifications
supplied herein are subject to change without notice at any time.
Copyright © Shanghai Quectel Wireless Solutions Ltd. 2012.
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Contents
Contents...................................................................................................................................................3
Table Index ..............................................................................................................................................5
Figure Index ............................................................................................................................................6
0. Revision history..................................................................................................................................8
1. Introduction .......................................................................................................................................9
1.1. Related documents....................................................................................................................9
1.2. Terms and abbreviations.........................................................................................................10
1.3. Safety cautions........................................................................................................................12
2. Product concept .............................................................................................................................15
2.1. Key features ............................................................................................................................15
2.2. Functional diagram.................................................................................................................17
2.3. Evaluation board.....................................................................................................................18
3. Application interface......................................................................................................................19
3.1. Pin of module..........................................................................................................................20
3.1.1. Pin assignment..............................................................................................................20
3.1.2. Pin description..............................................................................................................22
3.2. Operating modes.....................................................................................................................29
3.3. Power supply...........................................................................................................................30
3.3.1. Power features of module ............................................................................................30
3.3.2. Decrease supply voltage drop......................................................................................30
3.3.3. Reference design for power supply.............................................................................31
3.3.4. Monitor power supply..................................................................................................32
3.4. Power on and down scenarios................................................................................................32
3.4.1. Power on .......................................................................................................................32
3.4.2. Power down..................................................................................................................34
3.4.3. Restart ...........................................................................................................................36
3.5. Charge interface......................................................................................................................38
3.6. Power saving...........................................................................................................................38
3.6.1. Minimum functionality mode......................................................................................38
3.6.2. SLEEP mode.................................................................................................................39
3.6.3. Wake up module from SLEEP mode..........................................................................39
3.7. Summary of state transition ...................................................................................................39
3.8. RTC backup.............................................................................................................................40
3.9. Serial interfaces ......................................................................................................................41
3.9.1. UART Port....................................................................................................................42
3.9.2. Debug Port....................................................................................................................46
3.9.3. Auxiliary UART Port...................................................................................................46
3.9.4. UART application ........................................................................................................47
3.10. Audio interfaces....................................................................................................................50
3.10.1. Decrease TDD noise and other noise........................................................................51
3.10.2. Microphone interfaces design....................................................................................51
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3.10.3. Receiver and speaker interface design......................................................................52
3.10.4. Earphone interface design..........................................................................................54
3.10.5. Loud speaker interface design...................................................................................54
3.10.6. Audio characteristics..................................................................................................55
3.11. SIM card interface ................................................................................................................55
3.11.1. SIM card application..................................................................................................55
3.11.2. 6 Pin SIM cassette......................................................................................................57
3.11.3. 8 Pin SIM cassette......................................................................................................58
3.12. SD card interface ..................................................................................................................60
3.13. PCM interface.......................................................................................................................62
3.13.1. Configuration..............................................................................................................62
3.13.2. Timing.........................................................................................................................63
3.13.3. Reference design ........................................................................................................64
3.13.4. AT command..............................................................................................................64
3.14. ADC.......................................................................................................................................66
3.15. Behaviors of the RI...............................................................................................................66
3.16. Network status indication.....................................................................................................69
3.17. Operating status indication ..................................................................................................69
4. Antenna interface...........................................................................................................................71
4.1. RF reference design................................................................................................................71
4.2. RF output power .....................................................................................................................72
4.3. RF receiving sensitivity..........................................................................................................72
4.4. Operating frequencies.............................................................................................................72
4.5. RF cable soldering..................................................................................................................73
5. Electrical, reliability and radio characteristics .........................................................................74
5.1. Absolute maximum ratings ....................................................................................................74
5.2. Operating temperature............................................................................................................74
5.3. Power supply ratings ..............................................................................................................75
5.4. Current consumption..............................................................................................................76
5.5. Electro-static discharge ..........................................................................................................78
6. Mechanical dimensions................................................................................................................79
6.1. Mechanical dimensions of module........................................................................................79
6.2. Recommended footprint without bottom centre pads ..........................................................81
6.4. Top view of the module .........................................................................................................82
6.5. Bottom view of the module....................................................................................................83
7. Storage and manufacturing.........................................................................................................84
7.1. Storage.....................................................................................................................................84
7.2. Soldering.................................................................................................................................85
7.3. Packaging................................................................................................................................86
Appendix A: GPRS coding schemes .............................................................................................87
Appendix B: GPRS multi-slot classes............................................................................................88
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Table Index
TABLE 1: RELATED DOCUMENTS .....................................................................................................9
TABLE 2: TERMS AND ABBREVIATIONS........................................................................................10
TABLE 3: MODULE KEY FEATURES................................................................................................15
TABLE 4: CODING SCHEMES AND MAXIMUM NET DATA R ATES OVER AIR INTERFACE..17
TABLE 5: M50 PIN ASSIGNMENT.....................................................................................................21
TABLE 6: PIN DESCRIPTION .............................................................................................................22
TABLE 7: OVERVIEW OF OPERATING MODES..............................................................................29
TABLE 8: PIN DEFINITION OF THE CHARGING............................................................................38
TABLE 9: SUMMARY OF STATE TRANSITION...............................................................................39
TABLE 10: LOGIC LEVELS OF THE UART INTERFACES..............................................................42
TABLE 11: PIN DEFINITION OF THE UART INTERFACES............................................................42
TABLE 12: PIN DEFINITION OF AUDIO INTERFACES ..................................................................50
TABLE 13: AOUT3 OUTPUTCHARACTERISTICS..........................................................................51
TABLE 14: TYPICAL ELECTRET MICROPHONE CHARACTERISTICS.......................................55
TABLE 15: TYPICAL SPEAKER CHARACTERISTICS....................................................................55
TABLE 16: PIN DEFINITION OF THE SIM INTERFACE.................................................................56
TABLE 17: PIN DESCRIPTION OF AMPHENOL SIM CARD HOLDER .........................................58
TABLE 18: PIN DESCRIPTION OF MOLEX SIM CARD HOLDER.................................................59
TABLE 19: PIN DEFINITION OF THE SD CARD INTERFACE .......................................................60
TABLE 20: PIN NAME OF THE SD CARD AND MICRO SD CARD...............................................61
TABLE 21: PIN DEFINITION OF PCM INTERFACE.........................................................................62
TABLE 22: CONFIGURATION ............................................................................................................62
TABLE 23: QPCMON COMMAND DESCRIPTION ..........................................................................65
TABLE 24: QPCMVOL COMMAND DESCRIPTION ........................................................................65
TABLE 25: PIN DEFINITION OF THE ADC.......................................................................................66
TABLE 26: CHARACTERISTICS OF THE ADC ................................................................................66
TABLE 27: BEHAVIORS OF THE RI ..................................................................................................66
TABLE 28: WORKING STATE OF THE NETLIGHT .........................................................................69
TABLE 29: PIN DEFINITION OF THE STATUS.................................................................................69
TABLE 30: PIN DEFINITION OF THE RF_ANT................................................................................71
TABLE 31: THE MODULE CONDUCTED RF OUTPUT POWER....................................................72
TABLE 32: THE MODULE CONDUCTED RF RECEIVING SENSITIVITY....................................72
TABLE 33: THE MODULE OPERATING FREQUENCIES................................................................72
TABLE 34: ABSOLUTE MAXIMUM RATINGS.................................................................................74
TABLE 35: OPERATING TEMPERATURE.........................................................................................74
TABLE 36: THE MODULE POWER SUPPLY RATINGS...................................................................75
TABLE 37: THE MODULE CURRENT CONSUMPTION..................................................................76
TABLE 38: THE ESD ENDURANCE (TEMPERATURE:25℃,HUMIDITY:45 %)............................78
TABLE 39: DESCRIPTION OF DIFFERENT CODING SCHEMES ..................................................87
TABLE 40: GPRS MULTI-SLOT CLASSES........................................................................................88
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Figure Index
FIGURE 1: MODULE FUNCTIONAL DIAGRAM .............................................................................18
FIGURE 2: PIN ASSIGNMENT............................................................................................................20
FIGURE 3: VOLTAGE RIPPLE DURING TRANSMITTING .............................................................30
FIGURE 4: REFERENCE CIRCUITFOR THE VBAT INPUT............................................................31
FIGURE 5: REFERENCE CIRCUITFOR POWER SUPPLY..............................................................31
FIGURE 6: TURN ON THE MODULE USING DRIVING CIRCUIT.................................................32
FIGURE 7: TURN ON THE MODULE USING KEYSTROKE...........................................................33
FIGURE 8: TIMING OF TURNING ON SYSTEM..............................................................................33
FIGURE 9: TIMING OF TURNING OFF THE MODULE...................................................................34
FIGURE 10: REFERENCE CIRCUITFOR EMERG_OFF BY USING DRIVING CIRCUIT............36
FIGURE 11: REFERENCE CIRCUITFOR EMERG_OFF BY USING BUTTON..............................36
FIGURE 12: TIMING OF RESTARTING SYSTEM ............................................................................37
FIGURE 13: TIMING OF RESTARTING SYSTEM AFTER EMERGENCY SHUTDOWN..............37
FIGURE 14: RTC SUPPLY FROM NON-CHARGEABLE BATTERY ...............................................40
FIGURE 15: RTC SUPPLY FROM RECHARGEABLE BATTERY....................................................40
FIGURE 16: RTC SUPPLY FROM CAPACITOR ................................................................................40
FIGURE 17: SEIKO XH414H-IV01E CHARGE CHARACTERISTICS.............................................41
FIGURE 18: REFERENCE DESIGN FOR FULL-FUNCTION UART................................................44
FIGURE 19: REFERENCE DESIGN FOR UART PORT.....................................................................44
FIGURE 20: REFERENCE DESIGN FOR UART PORTWITH HARDWARE FLOW CONTROL...45
FIGURE 21: REFERENCE DESIGN FOR FIRMWARE UPGRADE..................................................45
FIGURE 22: REFERENCE DESIGN FOR DEBUG PORT..................................................................46
FIGURE 23: REFERENCE DESIGN FOR AUXILIARY UART PORT...............................................47
FIGURE 24: LEVEL MATCH DESIGN FOR 3.3V SYSTEM..............................................................47
FIGURE 25: LEVEL MATCH DESIGN FOR 5V SYSTEM.................................................................48
FIGURE 26: LEVEL MATCH DESIGN FOR RS-232..........................................................................49
FIGURE 27: REFERENCE DESIGN FOR AIN1&AIN2......................................................................52
FIGURE 28: REFERENCE DESIGN FOR AOUT1..............................................................................52
FIGURE 29: HANDSET INTERFACE DESIGN FOR AOUT2 ...........................................................53
FIGURE 30: SPEAKER INTERFACE DESIGN WITH AN AMPLIFIER FOR AOUT2.....................53
FIGURE 31: EARPHONE INTERFACE DESIGN ...............................................................................54
FIGURE 32: LOUD SPEAKER INTERFACE DESIGN.......................................................................54
FIGURE 33: REFERENCE CIRCUITOF THE 8 PINS SIM CARD....................................................56
FIGURE 34: REFERENCE CIRCUITOF THE 6 PINS SIM CARD....................................................57
FIGURE 35: AMPHENOL C707 10M006 512 2 SIM CARD HOLDER..............................................58
FIGURE 36: MOLEX 91228 SIM CARD HOLDER ............................................................................59
FIGURE 37: REFERENCE CIRCUITOF SD CARD...........................................................................60
FIGURE 38: LONG SYNCHRONIZATION & SIGN EXTENSION DIAGRAM ...............................63
FIGURE 39: LONG SYNCHRONIZATION & ZERO PADDING DIAGRAM ...................................63
FIGURE 40: SHORT SYNCHRONIZATION & SIGN EXTENSION DIAGRAM..............................63
FIGURE 41: SHORT SYNCHRONIZATION & ZERO PADDING DIAGRAM .................................64
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FIGURE 42: REFERENCE DESIGN FOR PCM..................................................................................64
FIGURE 43: RI BEHAVIOR OF VOICE CALLING AS ARECEIVER ..............................................67
FIGURE 44: RI BEHAVIOR OF DATA CALLING AS ARECEIVER ................................................67
FIGURE 45: RI BEHAVIOR AS ACALLER........................................................................................67
FIGURE 46: RIBEHAVIOR OF URC OR SMS RECEIVED..............................................................68
FIGURE 47: REFERENCE DESIGN FOR NETLIGHT.......................................................................69
FIGURE 48: REFERENCE DESIGN FOR STATUS ............................................................................70
FIGURE 49: REFERENCE DESIGN FOR RF......................................................................................71
FIGURE 50: RF SOLDERING SAMPLE..............................................................................................73
FIGURE 51: M50 TOP AND SIDE DIMENSIONS..............................................................................79
FIGURE 52: M50 BOTTOM DIMENSIONS........................................................................................80
FIGURE 53: RECOMMENDED FOOTPRINT WITHOUT BOTTOM CENTRE PADS ....................81
FIGURE 55: TOP VIEW OF THE MODULE .......................................................................................82
FIGURE 56: BOTTOM VIEW OF THE MODULE..............................................................................83
FIGURE 57: PASTE APPLICATION ....................................................................................................85
FIGURE 58: RAMP-SOAK-SPIKE REFLOW PROFILE ....................................................................86
FIGURE 59: MODULE TRAY ..............................................................................................................86
FIGURE 60: RADIO BLOCK STRUCTURE OF CS-1, CS-2 AND CS-3 ...........................................87
FIGURE 61: RADIO BLOCK STRUCTURE OF CS-4........................................................................87
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0. Revision history
Revision Date Author Description of change
1.0 2011-12-20 Ray XU Initial
1.1 2012-02-03 Ray XU 1. Updated PCM interface
2. Updated SD interface
3. Updated charging interface
4. Updated timing of turning on the module
1.2 2012-07-20 Baly BAO 1. Deleted the USB interface
2. Deleted the camera interface
1.3 2012-10-22 Mountain ZHOU 1. Updated functional diagram
2. Updated reference design circuit
3. Updated audio characteristics
4. Updated VRTC DC characteristics
5. Updated SLEEP current consumption
6. Updated internet service protocols
7. Updated SIM pins’ name
8. Modified PCM function
9. Deleted FAX function
2.0 2012-06-16 Ray XU 1. Update the module size
2. Update the pin layout
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1. Introduction
This document defines the M50 module and describes the hardware interface of M50 which are
connected with the customer application and the air interface.
This document can help customers quickly understand module interface specifications, electrical
and mechanical details. Associated with application notes and user guide, customers can use
M50module to design and set up mobile applications easily.
1.1. Related documents
Table 1: Related documents
SN Document name Remark
[1] M50_ ATC AT commands set
[2] ITU-T
Draft new
recommendation V.25ter
Serial asynchronous automatic dialing and control
[3] GSM 07.07
Digital cellular telecommunications (Phase 2+); AT
command set for GSM Mobile Equipment (ME)
[4] GSM 07.10 Support GSM 07.10 multiplexing protocol
[5] GSM 07.05 Digital cellular telecommunications (Phase 2+); Use
of Data Terminal Equipment –
Data Circuit
terminating Equipment (DTE –
DCE) interface for
Short Message Service (SMS) and Cell Broadcast
Service (CBS)
[6] GSM 11.14 Digital cellular telecommunications (P
hase 2+);
Specification of the SIM Application Toolkit for the
Subscriber Identity module – Mobile Equipment (SIM
– ME) interface
[7] GSM 11.11
Digital cellular telecommunications (Phase 2+);
Specification of the Subscriber Identity module –
Mobile Equipment (SIM – ME) interface
[8] GSM 03.38
Digital cellular telecommunications (Phase 2+);
Alphabets and language-specificinformation
[9] GSM 11.10 Digital cellular telecommunications (Phase 2); Mobile
Station (MS) conformance specification; Part 1:
Conformance specification
[10] GSM_UART_AN UART port application note
[11] GSM_FW_Upgrade_AN01 GSM Firmware upgrade application note
[12] M10_EVB_UGD M10 EVB user guide
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1.2. Terms and abbreviations
Table 2: Terms and abbreviations
Abbreviation Description
ADC Analog-to-Digital Converter
AMR Adaptive Multi-Rate
ARP Antenna Reference Point
ASIC Application Specific Integrated Circuit
BER Bit Error Rate
BOM Bill Of Material
BTS Base Transceiver Station
CHAP Challenge Handshake Authentication Protocol
CS Coding Scheme
CSD Circuit Switched Data
CTS Clear To Send
DAC Digital-to-Analog Converter
DRX Discontinuous Reception
DSP Digital Signal Processor
DCE Data Communications Equipment (typically module)
DTE Data Terminal Equipment (typically computer, external controller)
DTR Data Terminal Ready
DTX Discontinuous Transmission
EFR Enhanced Full Rate
EGSM Enhanced GSM
EMC Electromagnetic Compatibility
ESD ElectrostaticDischarge
ETS European Telecommunication Standard
FCC Federal Communications Commission (U.S.)
FDMA Frequency Division Multiple Access
FR Full Rate
GMSK Gaussian Minimum Shift Keying
GPRS General Packet Radio Service
GSM Global System for Mobile Communications
HR Half Rate
I/O Input/Output
IC Integrated Circuit
IMEI International Mobile Equipment Identity
Imax Maximum Load Current
Inorm Normal Current
kbps Kilo Bits Per Second
LED Light Emitting Diode
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Li-Ion Lithium-Ion
MO Mobile Originated
MS Mobile Station (GSM engine)
MT Mobile Terminated
PAP Password Authentication Protocol
PBCCH Packet Switched Broadcast Control Channel
PCB Printed Circuit Board
PDU Protocol Data Unit
PPP Point-to-Point Protocol
RF Radio Frequency
RMS Root Mean Square (value)
RTC Real Time Clock
RX Receive Direction
SIM Subscriber Identification Module
SMS Short Message Service
TDMA Time Division Multiple Access
TE Terminal Equipment
TX Transmitting Direction
UART Universal Asynchronous Receiver & Transmitter
URC Unsolicited Result Code
USSD Unstructured Supplementary Service Data
VSWR Voltage Standing Wave Ratio
Vmax Maximum Voltage Value
Vnorm Normal Voltage Value
Vmin Minimum Voltage Value
VIHmax Maximum Input High Level Voltage Value
VIHmin Minimum Input High Level Voltage Value
VILmax Maximum Input Low Level Voltage Value
VILmin Minimum Input Low Level Voltage Value
VImax Absolute Maximum Input Voltage Value
VImin Absolute Minimum Input Voltage Value
VOHmax Maximum Output High Level Voltage Value
VOHmin Minimum Output High Level Voltage Value
VOLmax Maximum Output Low Level Voltage Value
VOLmin Minimum Output Low Level Voltage Value
Phonebook abbreviations
LD SIM Last Dialing phonebook (list of numbers most recently dialed)
MC Mobile Equipment list of unanswered MT Calls (missed calls)
ON SIM (or ME) Own Numbers (MSISDNs) list
RC Mobile Equipment list of Received Calls
SM SIM phonebook
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1.3. Safety cautions
The following safety precautions must be observed during all phases of the operation, such as
usage, service or repair of any cellular terminal or mobile incorporating M50module.
Manufacturers of the cellular terminal should send the following safety information to users and
operating personnel and to incorporate these guidelines into all manuals supplied with the product.
If not so, Quectel does not take on any liability for customer failure to comply with these
precautions.
When in a hospital or other health care facility, observe the restrictions about the
use of mobile. Switch the cellular terminal or mobile off. Medical equipment may
be sensitive to not operate normally for RF energy interference.
Switch off the cellular terminal or mobile before boarding an aircraft. Make sure
it switched off. The operation of wireless appliances in an aircraft is forbidden to
prevent interference with communication systems. Forget to think much of these
instructions may lead to the flight safety or offend against local legal action, or
both.
Do not operate the cellular terminal or mobile in the presence of flammable gas
or fume. Switch off the cellular terminal when you are near petrol
station, fuel
depot, chemical plant or where blasting operations are in progress. Operation of
any electrical equipment in potentially explosive atmosphere can constitute a
safety hazard.
Your cellular terminal or mobile receives and transmits radio frequency energy
while switched on. RF interference can occur if it is used close to TV set, radio,
computer or other electric equipment.
Road safety comes first! Do not use a hand-held cellular terminal or mobile while
driving a vehicle, unless it is securely mounted in a holder for hands-free
operation. Before making a call with a hand-held terminal or mobile, park the
vehicle.
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According to the R&TTE Directive 1999/95/CE, all wireless equipment and
telecommunications terminals sold in EU must meet all the stipulated health,
safety RF, EMC requirements that provide for CE mark. Quectel Module M50
is fully in accordance with all the directives of EU.
1.4. Directives and standards
The M50 module is designed to comply with the FCC statements. FCC ID: XMR201211M50.
The Host system using M50, should have label indicated contains FCC ID: XMR201211M50.
1.4.1. FCC Statement
1. This device complies with Part 15 of the FCC rules. Operation is subject to the following
conditions:
a) This device may not cause harmful interference.
b) This device must accept any interference received, including interference that may cause
undesired operation.
2. Changes or modifications not expressly approved by the party responsible for compliance
could void the user’s authority to operate the equipment.
1.4.2. FCC Radiation exposure statement
This equipment complies with FCC radiation exposure limits set forth for an uncontrolled
environment. This equipment should be installed and operated with minimum distance 20cm
between the radiator and your body as well as kept minimum 20cm from radio antenna depending
on the Mobile status of this module usage.
GSM cellular terminals or mobiles operate over radio frequency signal and
cellular network and cannot be guaranteed to connect in all conditions, for
example no mobile fee or an invalid SIM card. While you are in this condition
and need emergent help, Please Remember using emergency call. In order to
make or receive call, the cellular terminal or mobile must be switched on and in
a service area with adequate cellular signal strength.
Some networks do not allow for emergency call if certain network services or
phone features are in use (e.g. lock functions, fixed dialing etc.). You may have
to deactivate those features before you can make an emergency call.
Also, some networks require that a valid SIM card be properly inserted in
cellular terminal or mobile.
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The manual of the host system, which uses M50, must include RF exposure warning statement to
advice user should keep minimum 20cm from the radio antenna of M50 module depending on the
Mobile status.
The following list of antenna is indicating the maximum permissible antenna gain.
Type Maximum Gain
(850Hz/900Hz) Maximum Gain (1800Hz/1900Hz) Impedance
External
Antenna
Monopole 0.5dBi 2dBi 50Ω
Vehicular antenna 0.5dBi 2dBi 50Ω
Internal
Antenna
Monopole 0.5dBi 2dBi 50Ω
PIFA 0.5dBi 2dBi 50Ω
FPC 0.5dBi 2dBi 50Ω
PCB 0.5dBi 2dBi 50Ω
This radio module must not be installed to co-locate and operate simu
ltaneously with other radios in host system;
additional testing and equipment authorization may be required to op
erating simultaneously with other radios.
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2. Product concept
M50 is a Quad-band GSM/GPRS engine that works at frequencies of GSM850MHz,
GSM900MHz, DCS1800MHz and PCS1900MHz. The M50 features GPRS multi-slot class 12
and supports the GPRS coding schemes CS-1, CS-2, CS-3 and CS-4. For more details about
GPRS multi-slot classes and coding schemes, please refer to the Appendix A and Appendix B.
With a tiny profile of 24.5mm×25.3mm×2.6mm, the module can meet almost all the requirements
for M2M applications, including Vehicles and Personal Tracking, Security System, Wireless POS,
Industrial PDA, Smart Metering, and Remote Maintenance & Control etc.
M50 is an SMD type module with LCC package, which can be embedded in customer’s
applications. It provides abundant hardware interfaces between the module and customer’s host
board.
Designed with power saving technique, the current consumption of M50 is as low as 1.3 mA in
SLEEP mode when DRX is 5.
M50 is integrated with Internet service protocols, such as TCP, UDP, FTP and PPP. Extended AT
commands have been developed for customer to use these Internet service protocols easily.
The module fully complies with the RoHS directive of the European Union.
2.1. Key features
Table 3: Module key features
Feature Description
Power supply Single supply voltage 3.3V~ 4.6V
Typical supply voltage 4.0V
Power saving Typical power consumption in SLEEP mode: 1.3 mA@ DRX=5
1.2 mA@ DRX=9
Frequency bands Quad-band: GSM850, GSM900, DCS1800, PCS1900.
The module can search these frequency bands automatically
The frequency bands can be set by AT command.
Compliant with GSM Phase 2/2+
GSM class Small MS
Transmitting power Class 4 (2W) at GSM850 and GSM900
Class 1 (1W) at DCS1800 and PCS1900
GPRS connectivity GPRS multi-slot class 12 (default)
GPRS multi-slot class 1~12 (configurable)
GPRS mobile station class B
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Temperature range Normal operation: -35°C ~ +80°C
Restricted operation: -40°C ~ -35°C and +80°C ~ +85°C 1)
Storage temperature: -45°C ~ +90°C
DATA GPRS:
CSD:
GPRS data downlink transfer: max. 85.6 kbps
GPRS data uplink transfer: max. 85.6 kbps
Coding scheme: CS-1, CS-2, CS-3 and CS-4
Support the protocols PAP (Password Authentication Protocol)
usually used for PPP connections
Internet service protocols
TCP/UDP/FTP/PPP/HTTP/NTP/PING
Support Packet Broadcast Control Channel (PBCCH)
CSD transmission rates: 2.4, 4.8, 9.6, 14.4 kbps non-transparent
Support Unstructured Supplementary Service Data (USSD)
SMS Text and PDU mode
SMS storage: SIM card
SIM interface Support SIM card: 1.8V, 3V
Audio features Speech codec modes:
Half Rate (ETS 06.20)
Full Rate (ETS 06.10)
Enhanced Full Rate (ETS 06.50 / 06.60 / 06.80)
Adaptive Multi-Rate (AMR)
Echo Suppression
Echo Cancellation
Noise Reduction
Embedded one amplifier of class AB with maximum driving
power up to 800mW
UART interfaces UART Port:
Seven lines on UART port interface
Used for AT command, GPRS data and CSD data
Multiplexing function
Support autobauding from 4800 bps to 115200 bps
Debug Port:
Two lines on debug port interface DBG_TXD and DBG_RXD
Debug Port only used for firmware debugging
Auxiliary Port:
Used for AT command
Phonebook management Support phonebook types: SM, ME, ON, MC, RC, DC, LD, LA
SIM Application Toolkit Support SAT class 3, GSM 11.14 Release 99
Real time clock Supported
Physical characteristics Size:
24.5 (±0.15) ×25.3 (±0.15) ×2.6 (±0.2) mm
Weight: 3.3g
Firmware upgrade Firmware upgrade via UART Port
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Antenna interface Connected to antenna pad with 50 Ohm impedance control
1 ） When the module works in this temperature range, the deviations from the GSM specification
may occur. For example, the frequency error or the phase error will be increased.
Table 4: Coding schemes and maximum net data rates over air interface
Coding scheme 1 Timeslot 2 Timeslot 4 Timeslot
CS-1 9.05kbps 18.1kbps 36.2kbps
CS-2 13.4kbps 26.8kbps 53.6kbps
CS-3 15.6kbps 31.2kbps 62.4kbps
CS-4 21.4kbps 42.8kbps 85.6kbps
2.2. Functional diagram
The following figure shows a block diagram of the M50 module and illustrates the major
functional parts:
Power management
Baseband
Serial Flash
The radio frequency part
The peripheral interface
—Charge interface
—PCM interface
—SD interface
—SIM interface
—Audio interface
—Serial interface
—Power supply
—RF interface
—ADC
—Turn on/off interface (PWRKEY & EMERG_OFF)
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BB&RF
RF PAM
SAW
Filter
Serial
Flash
32KHz
26MHz
RF Transceiver
Audio
RTC
GPIO
Serial
Interface Memory
Interface
PCM
Interface
SIM
Interface
SD
Interface
ADC
RF_ANT
VBAT
PWRKEY
EMERG_OFF
VRTC
ADC
STATUS&
NETLIGHT
UART
SIM
Interface
Audio
SD
Interface
PCM
Inteface
Reset
ESD
PMU
Charge
Interface Charge
Figure 1: Module functional diagram
2.3. Evaluation board
In order to help customer to develop applications with M50 , Quectel supplies an evaluation board
(EVB), RS-232 to USB cable, power adapter, earphone, antenna and other peripherals to control
or test the module. For details, please refer to the document [12].
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3. Application interface
The module is equipped with 83-pin SMT pads and it adopts LCC package. Detailed descriptions
on Sub-interfaces included in these pads are given in the following chapters:
Power supply
Power on/down
Charge interface
RTC
Serial interfaces
Audio interfaces
SIM interface
SD interface
PCM interface
ADC
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3.1. Pin of module
3.1.1. Pin assignment
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
575859606162636465666768697071727374
Top view
75
76
77
78
79
80
81
82
83
SIM_PRESENCE
RESERVED
VRTC
VDD_EXT
GND
GND
RF_ANT
GND GND GND
VBAT VBAT VBAT
VBAT
RESERVED
RESERVED
RESERVED
RESERVED
ADC1
ADC0
RESERVED
NETLIGHT
SPK2P
AGND
MIC2P
MIC2N
MIC1P
MIC1N
SPK1N
SPK1P
LOUDSPKN
LOUDSPKP
STATUS
PWRKEY
EMERG_OFF
PCM_IN
PCM_CLK RESERVED
RESERVED
TXD_AUX
RXD_AUX
DBG_TXD
DBG_RXD
RESERVED
DCD
RI
DTR
CTS
RTS
RXD
TXD
SIM1_GND
SIM1_RST
SIM1_CLK
SIM1_DATA
SIM1_VDD
VBAT GND PCM RF UART
Power SIM Reserved Audio
ADC
Other
SD
PCM_OUT
PCM_SYNC
RESERVED RESERVED RESERVED RESERVED RESERVED RESERVED RESERVED RESERVED RESERVED
RESERVED
RESERVED
RESERVED
SD_CMD
SD_CLK
SD_DATA0
GND
RESERVED
RESERVED
RESERVED
RESERVED
GND
GND
GND
GND
Figure 2: Pin assignment
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