Page 2
Furthermore, system validation of this product designed by SIMCom 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.
Page 5
SIM802 Hardware Design Table Index TABLE 1: RELATED DOCUMENTS....................9 TABLE 2: TERMS AND ABBREVIATIONS ..................10 TABLE 3: SIM802 KEY FEATURES....................15 TABLE 4: CODING SCHEMES AND MAXIMUM NET DATA RATES OVER AIR INTERFACE. 16 TABLE 5: PIN DESCRIPTION ......................19 TABLE 6: OVERVIEW OF OPERATING MODES................
Page 6
SIM802 Hardware Design Figure Index FIGURE 1: SIM802 FUNCTIONAL DIAGRAM ................17 FIGURE 2: TOP VIEW OF SIM802 EVB .................... 18 FIGURE 3: VBAT INPUT ......................... 24 FIGURE 4: REFERENCE CIRCUIT OF THE SOURCE POWER SUPPLY INPUT......25 FIGURE 5: VBAT VOLTAGE DROP DURING TRANSMIT BURST ..........25 FIGURE 6: TURN ON SIM802 USING DRIVING CIRCUIT ............
SIM802 Hardware Design FIGURE 44: TOP VIEW OF SIM802 ....................71 FIGURE 45: THE RAMP-SOAK-SPIKE REFLOW PROFILE OF SIM802........72 SIM802_HD_V2.01 12.01.2010...
Origin Jirang Feng Scope of the document This document is intended for the following versions of the SIMCom modules •SIM802-A: GSM/GPRS 900/1800 MHz and 850/1900MHz, SRD RF 433MHz Version SIM802-B: GSM/GPRS 900/1800 MHz and 850/1900MHz, SRD RF 868MHz Version SIM802-C: GSM/GPRS 900/1800 MHz and 850/1900MHz, SRD RF 915MHz Version SIM802_HD_V2.01...
SIM802 Hardware Design 1 Introduction This document describes the hardware interface of the SIMCom SIM802 module that connects to the specific application and the air interface. As SIM802 can be integrated with a wide range of applications, all functional components of SIM802 are described in great detail.
SIM802 Hardware Design 1.2 Terms and abbreviations Table 2: 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 11
SIM802 Hardware Design kbps Kilo bits per second Light Emitting Diode 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...
If not so, SIMCom 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 mobiles.
Page 13
SIM802 Hardware Design 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 sets, radios, computers or other electric equipment. 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.
SIM802 Hardware Design 2 Product concept Designed for global market, SIM802 module is a complete Quad-Band GSM/GPRS solution that is also equipped with SRD RF technology and embedded SIM card IC (optional).The GSM/GPRS engine works on frequencies GSM/GPRS 900/1800 MHz and 850/1900MHz, SIM802 series features GPRS multi-slot class 10/Class 8 (the default is class 10) capability and supports the GPRS coding schemes CS-1, CS-2, CS-3 and CS-4.
SIM802 Hardware Design 2.1 SIM802 key features at a glance Table 3: SIM802 key features Feature Implementation Power supply Single supply voltage 3.4V – 4.5V Power saving Typical power consumption in SLEEP mode to 6mA ( BS-PA-MFRMS=5 ) Charging Supports charging control for Li-Ion battery GSM frequency Bands SIM802 quad-band: GSM/GPRS 900/1800 MHz and 850/1900MHz.
SIM802 Hardware Design Enhanced Full Rate (ETS 06.50 / 06.60 / 06.80) Adaptive multi rate (AMR) Echo Cancellation Serial interface and Serial Port: Seven lines on Serial Port Interface Debug interface Serial Port can be used for CSD FAX, GPRS service and sending AT command of controlling module.
SIM802 Hardware Design 2.2 SIM802 functional diagram The following figure shows a functional diagram of the SIM802 and illustrates the mainly functional part: The GSM baseband engine Flash and SRAM The GSM radio frequency part The GSM antenna interface The SRD radio frequency part The SRD RF antenna interface The embedded SIM card IC (optional) The other external interfaces...
SIM802 Hardware Design 2.3 SIM802 evaluation board In order to help you on the application of SIM802, SIMCom can supply an Evaluation Board (EVB) that interfaces the SIM802 directly with appropriate power supply, SIM card holder, the main serial port and debug serial port, handset port, LCD (optional), antenna and all GPIO of the SIM802.
SIM802 Hardware Design 3 Application interface All hardware interfaces are described in detail in following chapters: Power supply and charging control (see Chapters 3.3 and 3.5) Provide main serial interface and debug serial interface (see chapter3.9) Two analog audio interfaces (see chapter 3.10) SIM interface (see chapter 3.11) LCD interface (see chapter 3.12) GPIO interface (see chapter 3.13)
Page 20
SIM802 Hardware Design the system. Vnorm=1.8V connected Current output for backup = 20uA battery out(max) battery when the main =5 uA capacitor. battery is present and the backup battery is in low voltage state. VCHG Voltage input for the charge Vmax=5.25V If unused keep pin circuit, as the signal for...
Page 21
SIM802 Hardware Design Pin name Description DC characteristics Comment STATUS Indicate work status VOLmin=GND unused keep VOLmax=0.2V pins open VOHmin= 2.93V-0.2 VOHmax= 2.93V GPIO General Input Output Port DISP_DAT Display interface unused keep pins open DISP _CLK DISP _CS DISP _D/C DISP _RST KBR0 Pull up inside, if...
Page 22
SIM802 Hardware Design diode array. VIHmax= SIM_VDD+0.3 VOLmin=GND VOLmax=0.2V VOHmin= SIM_VDD-0.2 VOHmax= SIM_VDD Pin Name Description DC characteristics Comment ADC0 General purpose analog to Input voltage value unused keep digital converter. scope 0V to 2.4V pins open TEMP_BA Measure battery temperature SRD interface Pin name...
SIM802 Hardware Design 3.2 Operating modes The table below briefly summarizes the various operating modes referred to in the following chapters. Table 6: Overview of operating modes Mode Function GSM/GPRS Module will automatically go into SLEEP mode if DTR is set to high SLEEP level and there is no on air or audio activity is required and no hardware interrupt (such as GPIO interrupt or data on serial port).
SIM802 Hardware Design serial interfaces is still accessible. The power consumption in this case is very low. Alarm mode RTC alert function launches this restricted operation while the module is in POWER DOWN mode. SIM802 will not be registered to GSM network and only parts of AT commands can be available.
SIM802 Hardware Design is drained. The following figure is the reference design of +5V input source power supply. The designed output for the power supply is 4V, thus a linear regulator can be used. If there’s a big difference between the input source and the desired output (VBAT), a switching converter power supply will be preferable because of its better efficiency especially with the 2A peak current in burst mode of the module.
SIM802 Hardware Design one analog GND pins are recommended for grounding. The VCHG Pin serves as a control signal for charging a Li-Ion battery. VRTC Pin can be used to back up the RTC. 3.3.2 Minimizing power losses Please pay special attention to the supply power when you are designing your applications. Please make sure that the input voltage will never drop below 3.4V even in a transmitting burst during which the current consumption may rise up to 2A.
Page 27
SIM802 Hardware Design 3.4.1.1 Turn on SIM802 using the PWRKEY Pin (Power on) Turn on the SIM802 by driving the PWRKEY to a low level voltage for a period time. This Pin is pulled up to VBAT in the module. The simple circuit illustrates as the following figures. PWRKEY 4.7K Turn on impulse...
SIM802 Hardware Design VBAT Pulldown > 2s > 0.6*VBAT PWRKEY (INPUT) <0.2*VBAT STATUS (OUTPUT) Figure 8 Timing of turn on system When power on procedure completed, SIM802 will send out following result code to indicate the module is ready to operate, when set as fixed baud rate. STATUS Pin will drive to 2.8V and keep this level when in work mode.
SIM802 Hardware Design From GHOST MODE to NORMAL MODE 3.4.1.3 Turn on SIM802 using the RTC (Alarm mode) Alarm mode is a power-on approach by using the RTC. The alert function of RTC makes the SIM802 wakeup while the module power off. In alarm mode, SIM802 will not register to GSM network and the software protocol stack is closed.
SIM802 Hardware Design over-voltage is detected Over-temperature or under-temperature automatic shutdown: Take effect if over-temperature or under-temperature is detected 3.4.2.1 Turn off SIM802 using the PWRKEY Pin (Power down) You can turn off the SIM802 by driving the PWRKEY to a low level voltage for a period time. The power down scenarios illustrate as figure 9.
Page 31
SIM802 Hardware Design Please refer to document [1] for detail about the AT command of “AT+CPOWD”. 3.4.2.3 Over-voltage or under-voltage automatic shutdown The module will constantly monitor the voltage applied on the VBAT. If the voltage ≤ 3.5V, the following URC will be presented: UNDER-VOLTAGE WARNNING If the voltage ≥...
SIM802 Hardware Design After this moment, the AT commands can’t be executed. The module logs off from network and enters POWER DOWN mode, and only the RTC is still active. POWER DOWN can also be indicated by STATUS Pin, which is a low level voltage in this mode. To monitor the temperature, you can use the “AT+CMTE”...
SIM802 Hardware Design Figure 11: Battery charger and pack The function of detecting the temperature of battery should be supported by the software in the module. It’s a customization function. The R is a NTC thermistor. We recommend to use TEMP NCP15XH103F03RC from MURATA.
SIM802 Hardware Design 3.5.2 Recommended battery pack Following is the spec of recommended battery pack: Table 8: Spec of recommended battery pack Product name & type BYD, Li-Ion, 3.7V, 580mAh To obtain more information BYD COMPANY LIMITED Please contact : Normal voltage 3.7V Capacity...
SIM802 Hardware Design UVLO (under voltage lock out) means the battery voltage less than 3.2V and more than 2.4V. The battery is not suitable for fast charge when its condition is DDLO or UVLO. The SIM802 provides a small constant current to the battery when the battery is between DDLO and UVLO. In DDLO charge, SIM802 gives out 5mA current to the battery.
SIM802 Hardware Design Connect charger to module’s VCHG Pin Battery can be charged when GSM while SIM802 is in POWER DOWN engine is not registered to GSM mode. network; Only a few AT commands is available IMPORTANT: Here GHOST mode is as listed below.
SIM802 Hardware Design interface signal can be used to lead system to be SLEEP mode (or Slow clocking mode). 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;...
SIM802 Hardware Design When DTR is in high level, and there is no on air and audio activity is required and no hardware interrupt (such as GPIO interrupt or data on serial port), SIM802 will enter SLEEP mode automatically. In this mode, SIM802 can still receive paging or SMS from network. In SLEEP mode, the serial port is not accessible.
SIM802 Hardware Design AT+CPOWD or timer expire, using PWRKEY the module turn on and enter Alarm mode Ghost mode Disconnect No direct Turn on the module Set alarm by (Charge-only charger transition, but using PWRKEY OR “AT+CALAR mode) via “Charging SET AT Command M”, when the in normal”...
SIM802 Hardware Design Rechargeable Lithium coin cells such as the TC614 from Maxell, or the TS621 from Seiko, are also small in size, but have higher capacity than the double layer capacitors resulting in longer backup times. Typical charge curves for each cell type are shown in following figures. Note that the rechargeable Lithium type coin cells are generally pre-charged from the vendor.
SIM802 Hardware Design Figure 18: Seiko TS621 Charge Characteristic Capacitor backup Some suitable coin cells are the coin-type capacitors available from SEIKO (XH414H-IV01E), or from SHOEI (PAS414HR-VG1). They have a small physical size (4.8 mm diameter) and give hours of backup time. The specification of XH414H-IV01E is shown in following table.
SIM802 Hardware Design 3.9 Serial interfaces SIM802 provides two unbalanced asynchronous serial ports. One is the main serial port and the other is the debug serial port. The GSM module is designed as a DCE (Data Communication Equipment), following the traditional DCE-DTE (Data Terminal Equipment) connection. The module and the client (DTE) are connected through the following signal (as figure 19 shows).
SIM802 Hardware Design Figure 19: Connection of serial ports Note: The RTS PIN must be connected to the GND in the customer circuit when only the TXD and RXD are used in the Serial Port communication. 3.9.1 Main serial port and Debug serial port supporting Main serial port Seven lines on Serial Port Interface Contains Data lines TXD and RXD, State lines RTS and CTS, Control lines DTR, DCD and...
SIM802 Hardware Design 9600, 19200, 38400, 57600, 115200bps Note: You can use software to set a fixed baud rate and save the configuration to non-volatile flash memory. After the configuration was saved as fixed baud rate, the Unsolicited Result Codes like "RDY" should be received from the serial port all the time when the SIM802 was power on.
SIM802 Hardware Design Figure 21: Connection of software debug The main serial port and the debug serial port don’t support the RS_ level and it only supports the CMOS level. Please refer to the table 5 for details about the voltage level. You should add the level converter IC between the DCE and DTE.
SIM802 Hardware Design Table 15: MIC Input Characteristics Parameter Unit Working Voltage Working Current External k Ohms Microphone Load Resistance Table 16: Audio Output Characteristics Parameter Unit Normal Single load Output(SPK1) Ended Resistance Ref level 0.5477 -12.04 Differential load Resistance Ref level 1.0954 -6.02...
SIM802 Hardware Design The SIM interface is powered from an internal regulator in the module having normal voltage 3V. All pins reset as outputs driving low. Logic levels are as described in table Table 17: Signal of SIM interface Signal Description SIM_VDD SIM Card Power supply, it can identify automatically the SIM Card...
SIM802 Hardware Design 220nF SIM_VDD SIM_VDD SIM_CLK SIM_CLK SIM802 SIM_RST SIM_RST MODULE SIM CARD SIM_DATA SIM_DATA MOLEX-91228 Figure 27: SIM interface reference circuit with 6 pins SIM card 3.11.3 Design considerations for SIM card holder For 6 pins SIM card, we recommend to use Amphenol C707-10M006 512 2 .You can visit http://www.amphenol.com for more information about the holder.
SIM802 Hardware Design Figure 28: Amphenol C707-10M006 512 2 SIM card holder Table 18: Pin description (Amphenol SIM card holder) Signal Description SIM_VDD SIM Card Power supply, it can identify automatically the SIM Card power mode, one is 3.0V±10%, and another is 1.8V±10%.
SIM802 Hardware Design SIM Card Detect 0Ω pulled up to VEXT Connect to GND. Not connect. SIM_DATA SIM Card data I/O. SIM Card Detect 10KΩ pulled down to GND For 8 pins SIM card holder, we recommend to use Molex 91228.You can visit http://www.molex.com for more information about the holder.
DISP_RST LCD reset Note: This function is not supported in the default firmware. For more information, please contact SIMCom. 3.13 General purpose input & output (GPIO) SIM802 provides a limited number of General Purpose Input/Output signal Pin. Table 21: GPIO of SIM802...
SIM802 Hardware Design 3.15 Behaviors of the Ring line (The main serial interface only) Table 23: Behaviours of the Ring line State RI respond Standby HIGH Voice calling Change LOW, then: ( 1 ) Change to HIGH when establish calling. (...
SIM802 Hardware Design 3.16 Network status indication LED lamp The NETLIGHT Pin can be used to drive a network status indication LED lamp. The working state of this Pin is listed in table 24: Table 24: Working state of network status indication LED Pin State SIM802 function SIM802 is not running...
The reference circuit for SPI shown as following figure: SIM802 APPLICATION MODULE MISO MOSI SCLK Figure 34: SPI application of the SRD interface Note: This function is not supported in the default firmware. For more information, please contact SIMCom. SIM802_HD_V2.01 12.01.2010...
SIM802 Hardware Design 3.18 Buzzer The buzzer can be used to drive a buzzer to indicate incoming call. The output volume of buzzer can be set by “AT+CRSL”. The reference circuit for buzzer shown as following figure: VBAT 4.7K BUZZER Figure 35: Reference circuit of Buzzer Table 26: Buzzer output characteristics Parameter...
SIM802 Hardware Design 4 Antenna interface The Pin 45 is the GSM RF antenna pad. The RF interface has an impedance of 50Ω. The Pin 33 is the SRD RF antenna pad. The RF interface has an impedance of 50Ω. 4.1 Antenna installation 4.1.1 Antenna pad SIM802 provides RF antenna interface.
SIM802 Hardware Design 4.2 Module RF output power Table 27: SIM802 conducted RF output power Frequency EGSM900 33dBm ±2db 5dBm±5db GSM850 33dBm ±2db 5dBm±5db DCS1800 30dBm ±2db 0dBm±5db PCS1900 30dBm ±2db 0dBm±5db SRD-RF 18dBm 9dBm The SRD-RF output power can be programmed from 9dBm to 18dBm in 3dB steps. It can be easily set through AT command.
SIM802 Hardware Design 5 Electrical, reliability and radio characteristics 5.1 Absolute maximum ratings Absolute maximum rating for power supply and voltage on digital and analog pins of SIM802 are listed in table31: Table 31: Absolute maximum rating Parameter Unit Peak current of power supply RMS current of power supply (during one TDMA- frame) Voltage at digit pins -0.3...
SIM802 Hardware Design Voltage ripple Normal condition, power control level for Pout max @ f<200kHz @ f>200kHz IVBAT Average supply POWER DOWN mode current SLEEP mode ( BS-PA-MFRMS=5 ) IDLE mode GSM850/EGSM 900 18.7 DCS1800/PCS1900 TALK mode GSM850/EGSM 900 DCS1800/PCS1900 DATA mode GPRS, (3 Rx, 2 TX) GSM850/EGSM 900 DCS1800/PCS1900...
SIM802 Hardware Design 6 Mechanics This chapter describes the mechanical dimensions of SIM802. 6.1 Mechanical dimensions of SIM802 Following shows the mechanical dimensions of SIM802 (top view, side view and bottom view). All dimensions are shown in millimeters. Figure 37: SIM802 top view SIM802_HD_V2.01 12.01.2010...
SIM802 Hardware Design Figure 41: Footprint recommendation : Notes Keep out on the user mainboard below the test point and the keep out area, as these are solder mask. For maintain this module, the placement must be keep a distance between the module and other component about 3 mm, and the height of near components must less than 16mm.
SIM802 Hardware Design 6.3 The ramp-soak-spike reflow profile of SIM802 If both sides of the mainboard have SMD parts, the SIM802 module must be soldered last. Figure 45: The ramp-soak-spike reflow profile of SIM802 SIM802_HD_V2.01 12.01.2010...
Need help?
Do you have a question about the SIM802 HD and is the answer not in the manual?
Questions and answers