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SIM Tech SIM900D HD Manual

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Hardware Design
SIM900D_HD_V1.02

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  • Page 1 Hardware Design SIM900D_HD_V1.02...
  • Page 2 SIM900D Hardware Design SIM900D Hardware Design Document Title: 1.02 Version: 2010-04-09 Date: Release Status: SIM900D_HD_V1.02 Document Control ID: General Notes SIMCom offers this information as a service to its customers, to support application and engineering efforts that use the products designed by SIMCom. The information provided is based upon requirements specifically provided to SIMCom by the customers.

  • Page 3: Table Of Contents

    SIM900D Hardware Design Contents Contents ..................................3 Version history................................7 1 Introduction................................8 1.1 Related Documents ............................8 1.2 Terms and Abbreviations..........................9 1.3 Safety Precautions ............................11 2 SIM900D Overview..............................13 2.1 SIM900D Key Features..........................13 2.2 SIM900D Functional Diagram........................15 2.3 SIM900D Evaluation Board........................16 3 Application Interface.............................18 3.1 SIM900D Pin Description ...........................18 3.2 Operating Modes ............................21 3.3 Power Supply ..............................22...
  • Page 4 SIM900D Hardware Design 3.10.3 Earphone Interface Configuration ....................42 3.10.4 Referenced Electronic Characteristic ....................42 3.11 SIM Card Interface............................44 3.11.1 SIM Card Application........................44 3.11.2 Design Considerations for SIM Card Holder ..................45 3.12 LCD Display Interface ..........................46 3.13 ADC ................................46 3.14 Behaviors of the RI ...........................47 3.15 Network Status Indication .........................48 3.16 General Purpose Input Output (GPIO) ......................48 3.17 PWM .................................49...
  • Page 5 SIM900D Hardware Design Table Index TABLE1: RELATED DOCUMENTS ..........................8 TABLE2: TERMS AND ABBREVIATIONS ........................9 TABLE3: SIM900D KEY FEATURES..........................13 TABLE4: CODING SCHEMES AND MAXIMUM NET DATA RATES OVER AIR INTERFACE ......15 TABLE5: PIN DESCRIPTION ............................18 TABLE6: OVERVIEW OF OPERATING MODES......................21 TABLE7: SPECIFICATION OF RECOMMENDED BATTERY PACK.................
  • Page 6 SIM900D Hardware Design Figure Index FIGURE1: SIM900D FUNCTIONAL DIAGRAM ......................16 FIGURE2: TOP VIEW OF SIM900D EVB ........................17 FIGURE3: REFERENCE CIRCUIT OF THE VBAT INPUT ..................22 FIGURE4: REFERENCE CIRCUIT OF THE SOURCE POWER SUPPLY INPUT............23 FIGURE5: VBAT VOLTAGE DROP DURING TRANSMIT BURST ................23 FIGURE6: TURN ON SIM900D USING DRIVING CIRCUIT ..................

  • Page 7: Version History

    SIM900D Hardware Design Version history Date Version Description of change Author 2010-03-31 1.01 Origin Jing.zhou 2010-04-09 1.02 Changed GHOST mode to Charge-only mode §3.4.1.1Update the Figure8: Timing of turn on system using PWRKEY Jing.zhou §3.4.2.1Update the Figure9: Timing of turn off system using PWRKEY §4.2Update the Table25: SIM900D conducted RF receive sensitivity...

  • Page 8: Introduction

    SIM900D Hardware Design 1 Introduction This document describes the hardware interface of the SIMCom SIM900D module that connects to the specific application and the air interface. As SIM900D can be integrated with a wide range of applications, all functional components of SIM900D are described in great detail. This document can help you quickly understand SIM900D interface specifications, electrical and mechanical details.

  • Page 9: Terms And Abbreviations

    SIM900D Hardware Design 1.2 Terms and Abbreviations Table2: Terms and Abbreviations Abbreviation Description Analog-to-Digital Converter Adaptive Multi-Rate Antenna Reference Point ASIC Application Specific Integrated Circuit Bit Error Rate Base Transceiver Station CHAP Challenge Handshake Authentication Protocol Coding Scheme Circuit Switched Data Clear to Send Digital-to-Analog Converter Discontinuous Reception...
  • Page 10 SIM900D Hardware Design Abbreviation Description Li-Ion Lithium-Ion Mobile Originated Mobile Station (GSM engine), also referred to as TE Mobile Terminated Password Authentication Protocol PBCCH Packet Switched Broadcast Control Channel Printed Circuit Board Personal Communication System, also referred to as GSM 1900 Protocol Data Unit Point-to-point protocol Radio Frequency...

  • Page 11: Safety Precautions

    SIM900D Hardware Design Abbreviation Description Imax Maximum Load Current Phonebook abbreviations SIM fix dialing phonebook SIM last dialing phonebook (list of numbers most recently dialed) Mobile Equipment list of unanswered MT calls (missed calls) SIM (or ME) own numbers (MSISDNs) list Mobile Equipment list of received calls SIM phonebook Not connect...
  • Page 12 SIM900D Hardware Design Road safety comes first! Do not use a hand-held cellular terminal or mobile when 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. GSM cellular terminals or mobiles operate over radio frequency signals and cellular networks and cannot be guaranteed to connect in all conditions, for example no mobile fee or a invalid SIM card.

  • Page 13: Sim900D Overview

    SIM900D Hardware Design 2 SIM900D Overview Designed for global market, SIM900D is a quad-band GSM/GPRS engine that works on frequencies GSM 850MHz, EGSM 900MHz, DCS 1800MHz and PCS 1900MHz. SIM900D features GPRS multi-slot class 10/ class 8 (optional) and supports the GPRS coding schemes CS-1, CS-2, CS-3 and CS-4. With a tiny configuration of 33mm x 33mm x 3mm, SIM900D can meet almost all the space requirements in your applications, such as M2M, smart phone, PDA, FWP, and other mobile device.
  • Page 14 SIM900D Hardware Design Frequency Bands SIM900D Quad-band: GSM 850, EGSM 900, DCS 1800, PCS 1900. The SIM900D can search the 4 frequency bands automatically. The frequency bands also can be set by AT command. Compliant to GSM Phase 2/2+ GSM class Small MS Transmitting power Class 4 (2W) at GSM 850 and EGSM 900...

  • Page 15: Sim900D Functional Diagram

    SIM900D Hardware Design Debug port: 2-wire null modem interface DBG_TXD and DBG_RXD. Can be used for debugging and upgrading firmware. Phonebook management Support phonebook types: SM, FD, LD, RC, ON, MC. SIM Application Toolkit Support SAT class 3, GSM 11.14 Release 99 Real time clock Implemented Timer function...

  • Page 16: Sim900D Evaluation Board

    SIM900D Hardware Design Serial Port GPIO Battery Serial Battery GPIO Interface interface interface Debug/upgrading program Transceiver Power Amplifier Analog Controller With PMU 32.768KHz SIM interface Digital Baseband LCD interface 26MHz Flash+SRAM PWRKEY Analog interface Audio interface Charger Figure1: SIM900D functional diagram 2.3 SIM900D Evaluation Board In order to help you on the application of SIM900D, SIMCom can supply an Evaluation Board (EVB) that interfaces the SIM900D directly with appropriate power supply, SIM card holder, serial port, handset port,...

  • Page 17: Figure2: Top View Of Sim900D Evb

    SIM900D Hardware Design Figure2: Top view of SIM900D EVB For details please refer to the SIM900-EVB_UGD document. SIM900D_HD_V1.02 09.04.2010...

  • Page 18: Application Interface

    SIM900D Hardware Design 3 Application Interface SIM900D is equipped with a 48-pin SMT pad that connects to the cellular application platform. Sub-interfaces included in these SMT pads are described in detail in following chapters: Power supply and charging control (please refer to Chapter 3.3 and 3.5) Serial interface and Debug interface (please refer to chapter3.9) Two analog audio interfaces (please refer to Chapter 3.10) SIM interface (please refer to Chapter 3.11)
  • Page 19 SIM900D Hardware Design detecting charger Vnorm=5.0V inserting。 Ground Power on or power off PIN NAME DESCRIPTION DC CHARACTERISTICS PWRKEY Power on/off the system. VILmax=1.2V need an VIHmin=2.6V external pull-up VIHmax=3.3V resistor. VILmin= 0V Audio interfaces PIN NAME DESCRIPTION DC CHARACTERISTICS COMMENT MIC1P Positive and negative...
  • Page 20 SIM900D Hardware Design PIN NAME DESCRIPTION DC CHARACTERISTICS COMMENT Receive data VILmax=0.4V 1.DTR Pin has VIHmin=2.4V been pulled up. Transmit data VILmin= 0V 2.RXD should Request to send VIHmax= 3V be pulled up to Clear to send VOHmin= 2.7V 3V through a Ring indicator VOLmax=0.1V 10k resistor, if...

  • Page 21: Operating Modes

    SIM900D Hardware Design PWM Output VOHmin= 2.7V If unused keep VOLmax=0.1V open VOHmax= 3V VOLmin= 0V 3.2 Operating Modes The table below briefly summarizes the various operating modes referred to in the following chapters. Table6: Overview of operating modes Mode Function Normal GSM/GPRS...

  • Page 22: Power Supply

    SIM900D Hardware Design mode registered to GSM network and only limited AT commands can be accessible, the following way will enter Charge-only mode: From POWER DOWN mode: Connect charger to the module’s VCHG Pin and Battery connect VBAT Pin while SIM900D is power down. From Normal mode: Connect charger to the module’s VCHG Pin and Battery connect VBAT Pin, then power down the module by “AT+CPOWD”...

  • Page 23: Power Supply Pins

    SIM900D Hardware Design Figure4: Reference circuit of the source power supply input The following figure is the VBAT voltage drop at the maximum power transmit phase, the test condition is VBAT=4.0V, VBAT maximum output current =2A, C =100µF tantalum capacitor (ESR=0.7Ω) and C =1µF.

  • Page 24: Monitoring Power Supply

    SIM900D Hardware Design 3.3.3 Monitoring Power Supply To monitor the supply voltage, user can use the “AT+CBC” command which include three parameters: charging state, voltage percentage and voltage value (in mV). It returns charge state，the battery voltage 1-100 percent of capacity and actual value measured at VBAT and GND.
  • Page 25 SIM900D Hardware Design PWRKEY 4.7K Turn on impulse Figure6: Turn on SIM900D using driving circuit PWRKEY TVS1 Figure7: Turn on SIM900D using button The power on scenarios illustrates as following figure. Pulldown >1s Delay > 2.2s VBAT > 2.6V <1.2V PWRKEY (INPUT) >...

  • Page 26: Turn Off Sim900D

    SIM900D Hardware Design 3.4.1.2 Turn on the SIM900D using the VCHG signal As described in chapter 3.4, charger can be connected to SIM900D’s VCHG Pin regardless of the module’s operating mode. If the charger is connected to the module’s VCHG Pin while SIM900D is in POWER DOWN mode, SIM900D will go into the Charge-only Mode (Off and charging).

  • Page 27: Figure9: Timing Of Turn Off System Using Pwrkey

    SIM900D Hardware Design 5s>Pulldown >1s Delay > 1.7s PWRKEY (INPUT) Logout net > 2.6V <1.2V STATUS < 0.1V Figure9: Timing of turn off system using PWRKEY 3.4.2.2 Turn Off SIM900D Using AT Command The SIM900D can use the AT command “AT+CPOWD=1” to turn off the module. This command lets the module log off from the network and allows the module to enter into a secure state and save data before completely disconnecting the power supply.

  • Page 28: Restart Sim900D Using The Pwrkey Pin

    SIM900D Hardware Design URC will be presented: +CMTE:1 If the temperature < -30 , the fo ℃ llowing URC will be presented: +CMTE:-1 The uncritical temperature range is -40 ℃ +85 . If the temperature ℃ >+ 85 ℃ < -40 , the module will be ℃...

  • Page 29: Battery Pack Characteristics

    SIM900D Hardware Design C H G B A T M o d u le B a ttery P ack T E M P _ B A T T E M P T h erm isto r Figure11: Battery charger and pack The function of detecting the temperature of battery should be supported by the software in the module.

  • Page 30: Recommended Battery Pack

    SIM900D Hardware Design 3.5.2 Recommended battery pack Following is the specification of recommended battery pack: Table7: Specification of recommended battery pack Items Description Battery type Li-ion Manufacturer Jiade Energy Technology Normal voltage 3.7V Capacity NORMAL 1100mAh Charge Voltage 4.200±0.050V Max Charge Current 1.0C Charge Method CC / CV (Constant Current / Constant Voltage)

  • Page 31: Operating Modes During Charging

    SIM900D Hardware Design battery is between DDLO and UVLO. In DDLO charge, SIM900D gives out 1mA current to the battery. And in UVLO charge, SIM900D provides about less than 200mA current to the battery. DDLO charge terminated when the battery voltage reaches 1.5V. UVLO charge terminated when the battery voltage is up to 3.3V.

  • Page 32: Charger Requirements

    SIM900D Hardware Design Connect charger to module’s VCHG Pin Battery can be charged when GSM while SIM900D is in POWER DOWN engine is not registered to GSM mode. network; Only a few AT commands is available IMPORTANT: Here Charge-only mode is as listed below.

  • Page 33: Minimum Functionality Mode

    SIM900D Hardware Design 3.6.1 Minimum Functionality Mode Minimum functionality mode reduces the functionality of the module to a minimum and, thus, minimizes the current consumption to the lowest level. This mode is set with the “AT+CFUN” command which provides the choice of the functionality levels <fun>=0，1，4 0: minimum functionality;...

  • Page 34: Rtc Backup

    SIM900D Hardware Design AT+CPOWD or PWRKEY Power Down Power Down Normal Mode Normal Mode Mode Mode PWRKEY Insert charger Charge-only Charge-only Mode Mode State Transition Figure12: 3.8 RTC Backup The RTC (Real Time Clock) power supply of module can be provided by an external capacitor or a battery (rechargeable or non-chargeable) through the VRTC.

  • Page 35: Figure14: Rtc Supply From Rechargeable Battery

    SIM900D Hardware Design Module VRTC Core Rechargeable Backup Battery Figure14: RTC supply from rechargeable battery Module VRTC Core Large-capacitance Capacitor Figure15: RTC supply from capacitor Li-battery backup Coin-type Rechargeable Capacitor such as XH414H-IV01E form Seiko can be used. Typical charge curves for each cell type are shown in following figures. Note that the rechargeable Lithium type coin cells generally come pre-charged from the vendor.

  • Page 36: Serial Interfaces

    SIM900D Hardware Design 3.9 Serial Interfaces Table10: Pin definition of the serial interfaces Name Function Data terminal ready Ring indicator Data carrier detection Serial port Clear to send Request to send Transmit data Receive data DBG_RXD Receive data Debug port DBG_TXD Transmit data SIM900D provides two unbalanced asynchronous serial ports.

  • Page 37: Function Of Serial Port & Debug Port Supporting

    SIM900D Hardware Design MODULE (DCE) CUSTOMER (DTE) Serial port Serial port1 RING Debug port Serial port2 DBG_TX DBG_RX Figure17: Connection of the serial interfaces 3.9.1 Function of serial port & debug port supporting Serial port Modem device. Contains data lines TXD and RXD, State lines RTS and CTS, Control lines DTR, DCD and RI. Serial port can be used for CSD FAX, GPRS service and send AT command of controlling module.

  • Page 38: Software Upgrade And Software Debug

    SIM900D Hardware Design start up the ME while autobauding is enabled. This is due to the fact that the new baud rate is not detected unless DTE and DCE are correctly synchronized as described above. Note: Can use AT+IPR=x to set a fixed baud rate and save the configuration to non-volatile flash memory. After the configuration is saved as fixed baud rate, the Unsolicited Result Codes like "RDY"...

  • Page 39: Figure19: Rs232 Level Converter Circuit

    SIM900D Hardware Design MODULE Figure19: RS232 level converter circuit SIM900D_HD_V1.02 09.04.2010...

  • Page 40: Audio Interfaces

    SIM900D Hardware Design 3.10 Audio Interfaces Table12: Pin definition of the Audio interface Name Function (AIN1/AOUT1) MIC1P Microphone1 input + MIC1N Microphone1 input - SPK1P Audio1 output+ SPK1N Audio1 output- (AIN2/AOUT2) MIC2P Microphone2 input + MIC2N Microphone2 input - SPK2P Audio2 output+ SPK2N Audio2 output-...

  • Page 41: Speaker Interface Configuration

    SIM900D Hardware Design 3.10.1 Speaker Interface Configuration Close to speaker Differential layout MODULE ANTI 33pF 10pF SPK1P 10pF 33pF SPK1N ANTI 10pF 33pF Figure20: Speaker interface configuration Close to speaker MODULE Differential layout 10pF 33pF ANTI Amplifier Circuit SPK2P 10pF SPK2N ANTI 10pF...

  • Page 42: Microphone Interfaces Configuration

    SIM900D Hardware Design 3.10.2 Microphone Interfaces Configuration Close to Microphone MODULE Differential layout 10pF 33pF ANTI MIC1P Electret 10pF 33pF Microphone MIC1N 33pF ANTI 10pF Figure22: Microphone interface configuration 3.10.3 Earphone Interface Configuration Close to Socket Close to MODULE Differential layout 33pF 33pF...

  • Page 43: Table13: Mic Input Characteristics

    SIM900D Hardware Design Table13: MIC Input Characteristics Parameter Unit Working Voltage Working Current External Microphone Load Resistance k Ohms Internal biasing DC Characteristics Differential input 15.9 mVrms <1% voltage F=1KHz; pre-amp gain = 20 dB; PGA gain = 14 dB mVrms <5% F=1KHz;pre-amp...

  • Page 44: Sim Card Interface

    SIM900D Hardware Design RL=32 Ohm THD=0.1% RL=32 Ohm THD=1% 3.11 SIM Card Interface 3.11.1 SIM Card Application That can be use AT Command to get information in SIM card. For more information, please refer to document [1]. The SIM interface supports the functionality of the GSM Phase 1 specification and also supports the functionality of the new GSM Phase 2+ specification for FAST 64 kbps SIM (intended for use with a SIM application Tool-kit).

  • Page 45: Design Considerations For Sim Card Holder

    SIM900D Hardware Design 100nF CARD SIM_VDD SIM_RST SIM_CLK MODULE C707 10M006 512 2 SIM_DATA SMF05C Figure24: Reference circuit of the 6 pins SIM card 3.11.2 Design Considerations for SIM Card Holder For 6 pins SIM card holder, that be recommend to use Amphenol C707 10M006 512 2 .User can visit http://www.amphenol.com for more information about the holder.

  • Page 46: Lcd Display Interface

    SIM900D Hardware Design Table16: Pin description (Amphenol SIM card holder) Pin Name Signal Description SIM_VDD SIM Card Power supply, it can identify automatically the SIM Card power mode，one is 3.0V±10%, another is 1.8V±10%. Current is about 10mA. SIM_RST SIM Card Reset. SIM_CLK SIM Card Clock.

  • Page 47: Behaviors Of The Ri

    SIM900D Hardware Design 3.14 Behaviors of the RI Table19: Behaviours of the RI State RI respond Standby HIGH Voice calling Change LOW, then: （1）Change to HIGH when establish calling. （2）Use AT command ATH, the RI pin changes to HIGH. （3）Sender hangs up, change to HIGH. Data calling Change LOW, then：...

  • Page 48: Network Status Indication

    SIM900D Hardware Design 3.15 Network Status Indication The NETLIGHT can be used to drive a network status indication LED lamp. The working state of this pin is listed in following table: Table20: Working state of the NETLIGHT State SIM900D function SIM900D is not running 64ms On/ 800ms Off SIM900D does not find the network...

  • Page 49: Pwm

    SIM900D Hardware Design Table21: Pin definition of the GPIO interface Pin Name Pin Number Default Function Default State KBR0 GPIO8 Output Pull down GPO1 GPIO1 Output Pull down Note: This function is not supported in the default firmware. There must be customized firmware. Please contact SIMCom for more details.

  • Page 50: Antenna Interface

    SIM900D Hardware Design 4 Antenna Interface SIM900D provides RF antenna interface. And customer’s antenna should be located in the customer’s main board and connect to module’s antenna pad through microstrip line or other type RF trace which impendence must be controlled in 50Ω.

  • Page 51: Module Operating Frequencies

    SIM900D Hardware Design 4.3 Module Operating Frequencies Table26: SIM900D operating frequencies Frequency Receive Transmit GSM850 869 ～ 894MHz 824 ～ 849 MHz EGSM900 925 ～ 960MHz 880 ～ 915MHz DCS1800 1805 ～ 1880MHz 1710 ～ 1785MHz PCS1900 1930 ～ 1990MHz 1850 ～...

  • Page 52: Power Supply Ratings

    SIM900D Hardware Design 5.3 Power Supply Ratings Table29: SIM900D power supply ratings Parameter Description Conditions Unit VBAT Supply voltage Voltage must stay within the min/max values, including voltage drop, ripple, and spikes. Voltage drop Normal condition, power control level for during transmit Pout max burst...

  • Page 53: Current Consumption

    SIM900D Hardware Design Peak supply Power control level for Pout max. current (during Tx burst) 5.4 Current Consumption Please refer to the following table for the values of current consumption. Table30: SIM900D current consumption (VBAT=3.8V) Voice Call GSM 850/EGSM 900 @power level #5 <300mA,Typical 250mA @power level #10,Typical 110mA @power level #19,Typical 80mA...

  • Page 54: Electro-Static Discharge

    SIM900D Hardware Design 5.5 Electro-Static Discharge The GSM engine is not protected against Electrostatic Discharge (ESD) in general. Therefore, it is subject to ESD handing precautions that typically apply to ESD sensitive components. Proper ESD handing and packaging procedures must be applied throughout the processing, handing and operation of any application using a SIM900D module.

  • Page 55: Mechanics

    SIM900D Hardware Design 6 Mechanics This chapter describes the mechanical dimensions of SIM900D. 6.1 Mechanical Dimensions of SIM900D Following shows the Mechanical dimensions of SIM900D (top view, side view and bottom view). Dimensions shown in millimeters Figure29: SIM900D TOP view SIM900D_HD_V1.02 09.04.2010...

  • Page 56: Figure30: Sim900D Bottom View

    SIM900D Hardware Design Figure30: SIM900D bottom view Figure31: SIM900D SIDE view SIM900D_HD_V1.02 09.04.2010...

  • Page 57: Figure32: Footprint Recommendation

    SIM900D Hardware Design FOOT PRINT RECOMMENDATION: Figure32: Footprint recommendation SIM900D_HD_V1.02 09.04.2010...

  • Page 58: Top And Bottom View Of The Sim900D

    SIM900D Hardware Design 6.2 Top and Bottom View of the SIM900D Figure33: Top and Bottom view of the SIM900D 6.3 PIN Assignment of SIM900D DBG_RXD DBG_TXD STATUS SIM_DATA SIM_CLK SIM_RST SIM900D SIM_VDD TOP VIEW KBR0 PWRKEY DISP_CLK DISP_DATA VRTC DISP_D/C Figure34: SIM900D pin out diagram (Top View) SIM900D_HD_V1.02 09.04.2010...

  • Page 59: Table32: Pin Assignment

    SIM900D Hardware Design Table32: PIN Assignment Pin NUM NAME Pin NUM NAME DBG_RXD DBG_TXD STATUS SIM_DATA SIM_CLK SIM_RST SIM_VDD KBR0 PWRKEY DISP_CLK DISP_DATA VRTC DISP_D/C MIC2P MIC2N MIC1N MIC1P AGND SPK1P SPK1N SPK2N SPK2P TEMP_BAT VCHG ADC0 VBAT VBAT GPO1 NETLIGHT DISP_CS SIM900D_HD_V1.02...

  • Page 60: The Ramp-Soak-Spike Reflow Profile Of Sim900D

    SIM900D Hardware Design 6.4 The Ramp-Soak-Spike Reflow Profile of SIM900D Figure35: The ramp-soak-spike reflow profile of SIM900D SIM900D_HD_V1.02 09.04.2010...
  • Page 61 SIM900D Hardware Design Contact us: Shanghai SIMCom Wireless Solutions Ltd. Add: SIM Technology Building， No.633， Jinzhong Road， Changning District， Shanghai P.R. China 200335 Tel: +86 21 3235 3300 Fax: +86 21 3235 3301 URL: www.sim.com/wm SIM900D_HD_V1.02 09.04.2010...

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