SIM868_User Manual_REV2
Smart Machine Smart Decision 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. SIMCom has not undertaken any independent search for additional relevant information, including any information that may be in the customer’s possession.
Smart Machine Smart Decision Contents Version History ........................................................................................................ 9 1. Introduction .................................................................................................... 10 2. SIM868 Overview ........................................................................................... 10 2.1. 2.2. 2.3. 2.4. 3. Package Information ...................................................................
Smart Machine Smart Decision 4.8.2. 4.8.3. SIM Card Design Guide ...................................................................................................................... 36 Design Considerations for SIM Card Holder ...................................................................................... 37 4.9. SD Interface ................................................................................................................... 39 4.10. I2C Bus .......................................
Smart Machine Smart Decision 8. I. II. III. IV. Appendix ......................................................................................................... 57 Related Documents......................................................................................................... 57 Multiplexing Function .................................................................................................... 58 Terms and Abbreviations ....................................................................
Smart Machine Smart Decision Table Index TABLE 1: MODULE INFORMATION ......................................................................................................................10 TABLE 2: SIM868 KEY FEATURES .........................................................................................................................10 TABLE 3: GNSS ENGINE PERFORMANCE ............................................................................................................
Smart Machine Smart Decision TABLE 47: MULTIPLEXING FUNCTION................................................................................................................58 TABLE 48: TERMS AND ABBREVIATIONS ...........................................................................................................58 TABLE 49: SAFETY CAUTION ...............................................................................................................................60 SIM868_Hardware_Design_V1.
Smart Machine Smart Decision Figure Index FIGURE 1: SIM868 FUNCTIONAL DIAGRAM .......................................................................................................14 FIGURE 2: PIN OUT DIAGRAM (TOP VIEW).........................................................................................................15 FIGURE 3: DIMENSIONS OF SIM868 (UNIT: MM) ................................................................................................
Smart Machine Smart Decision Version History Date Version Description of change Author 2016-06-20 1.00 Origin Yanwu.Wang; Xiaoxu.Chen SIM868_Hardware_Design_V1.
Smart Machine Smart Decision 1. Introduction This document describes SIM868 hardware interface in great detail. The document can help customer to quickly understand SIM868 interface specifications, electrical and mechanical details. With the help of this document and other SIM868 application notes, customer guide, customers can use SIM868 to design various applications quickly. 2. SIM868 Overview Designed for global market, SIM868 is integrated with a high performance GSM/GPRS engine and a GNSS engine.
Smart Machine Smart Decision Feature Implementation Power supply 3.4V ~4.2V Power saving Typical power consumption in sleep mode is 0.65 mA (AT+CFUN=0 ) Quad-band: GSM 850, EGSM 900, DCS 1800, PCS 1900. SIM868 can search the 4 frequency bands automatically. The frequency bands can also be set by AT command “AT+CBAND”. For details, please refer to document [1].
Smart Machine Smart Decision Table 3: GNSS engine Performance Performance Parameter Description Horizontal Position Accuracy(1) Autonomous <2.5 m Without Aid 0.1 m/s DGPS 0.05 m/s Without Aid 0.1 m/s2 DGPS 0.05 m/s2 10 nS Velocity Accuracy(2) Acceleration Accuracy Min Timing Accuracy Backup batter voltage Dynamic Performance V_BACKUP Type 2.
Smart Machine Smart Decision NMEA Power consumption With GPS only mode(4) Acquisition 23.4 mA Continuous tracking 22.6 mA Sleep current 650 uA Power consumption With GLONASS only mode(4) Acquisition 24 mA Continuous tracking 21 mA Sleep current 650 uA Power consumption With GPS and GLONASS (4) Acquisition 31 mA Continuous tracking 26 mA Sleep current 650 uA (1) 50% 24hr static, -130dBm (2) 50% at 30m/s (3) GPS signal level: -130dBm (4) Single Power supply 3.
Smart Machine Smart Decision power consumption is related with network settings (e.g. power control level); uplink/downlink data rates and GPRS configuration (e.g. used multi-slot settings). Power off Normal power off by sending AT command “AT+CPOWD=1” or using the PWRKEY. The power management unit shuts down the power supply for the baseband part of the module. Software is not active. The serial port is not accessible. Power supply (connected to 3V) remains applied.
Smart Machine Smart Decision 3. Package Information 3.1. Pin Out Diagram Figure 2: Pin out Diagram (Top view) 3.2. Pin Description Table 6: Pin description Pin name Pin number I/O Description GPS_VBAT 34 I Power supply for GNSS VBAT 35 I Power supply for GSM VDD_EXT 40 O 2.8V power output Comment Power supply SIM868_Hardware_Design_V1.00 15 If these pins are unused, keep open.
Smart Machine Smart Decision GND 8,13,19,21,27,30, 31,33,36,37,45,63, 66,67,69,70,71,72, 73,74,75,76,77 Ground GND for VBAT recommend to use 36,37pin I PWRKEY should be pulled low and then released to power on/down the module. Internally pulled up to 3V. I Differential audio input Power on/down PWRKEY 39 Audio interfaces MICP 9 MICN 10 SPK1P 11 SPK1N 12 SPK2P 44 SPK2N 43 If these pins are unused, keep open.
Smart Machine Smart Decision UART1_RXD 2 I Receive data UART2_TXD 22 O Transmit data UART2_RXD 23 I Receive data USB_VBUS 24 I USB_DP 25 I/O USB_DM 26 I/O 38 SDA SCL Debug interface Debug and download If these pins are unused, keep open. I 10bit general analog to digital converter If these pins are unused, keep open. 64 I/O I2C serial bus data 65 O I2C serial bus clock Internal pulled up to 2.8V via 4.
Smart Machine Smart Decision 3.3. Package Dimensions Figure 3: Dimensions of SIM868 (Unit: mm) SIM868_Hardware_Design_V1.
Smart Machine Smart Decision Figure 4: Recommended PCB footprint outline (Unit: mm) SIM868_Hardware_Design_V1.
Smart Machine Smart Decision 4. Application Interface 4.1. Power Supply The power supply range of SIM868 is from 3.4V to 4.2V. Recommended voltage is 4.0V. The transmitting burst will cause voltage drop and the power supply must be able to provide sufficient current up to 2A. For the VBAT /GPS_VBAT input, a bypass capacitor (low ESR) such as a 100 µF is strongly recommended. For the VBAT/GPS_VBAT input, a 100uF Tantalum capacitor (CA low ESR) and a 1uF~10uF Ceramics capacitor CB are strongly recommended.
Smart Machine Smart Decision If there is a high drop-out between the input and the desired output (VBAT), a DC-DC power supply will be preferable because of its better efficiency especially with the 2A peak current in burst mode of the module. The following figure is the reference circuit. Figure 7: Reference circuit of the DC-DC power supply The single 3.7V Li-ion cell battery can be connected to SIM868 VBAT/GPS_VBAT pins directly.
Smart Machine Smart Decision Note: Hardware power off voltage is 3.0V. 4.1.2. Monitoring Power Supply AT command “AT+CBC” can be used to monitor the VBAT voltage. For detail, please refer to document [1]. 4.2. Power on/off SIM868 4.2.1. Power on SIM868 Customer can power on SIM868 by pulling down the PWRKEY pin for at least 1 second and release. This pin is already pulled up to 3V in the module internal, so external pull up is not necessary. Reference circuits are shown as below.
Smart Machine Smart Decision When power on procedure is completed, SIM868 will send following URC to indicate that the module is ready to operate at fixed baud rate. RDY This URC does not appear when autobauding function is active. Note: Customer can use AT command “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 Code “RDY” should be received from the serial port every time when SIM868 is powered on.
Smart Machine Smart Decision 4.2.2.2. Power off SIM868 by AT Command SIM868 can be powered off by AT command “AT+CPOWD=1”. This procedure makes the module log off from the network and allows the software to enter into a secure state to save data before completely shut down. Before the completion of the power off procedure, the module will send URC: NORMAL POWER OFF At this moment, AT commands can’t be executed any more.
Smart Machine Smart Decision 4.3. Power Saving Mode SIM868 has two power saving modes: Minimum functionality mode and sleep mode. AT command “AT+CSCLK=1”can be used to set SIM868 into sleep mode. AT command “AT+CFUN=“can be used to set SIM868 into minimum functionality. When SIM868 is in sleep mode and minimum functionality mode, the current of module is lowest. 4.3.1. Minimum Functionality Mode There are three functionality modes, which could be set by AT command “AT+CFUN=“.
Smart Machine Smart Decision command. 4.3.4. Sleep Mode 2 (AT+CSCLK=2) In this mode, SIM868 will continuously monitor the serial port data signal. When there is no data transfer over 5 seconds on the RXD signal and there is no on air and hardware interrupts (such as GPIO interrupt), SIM868 will enter sleep mode 2 automatically. In this mode, SIM868 can still receive paging or SMS from network. 4.3.5.
Smart Machine Smart Decision Rechargeable battery backup Figure 17: RTC supply from rechargeable battery 4.5. Serial Port and USB Interface SIM868 default provides one unbalanced asynchronous serial ports. The module is designed as a DCE (Data Communication Equipment). The following figure shows the connection between module and client (DTE).
Smart Machine Smart Decision VOH 4.5.1 2.4 - V Function of Serial Port Serial port: Full mode device. Contain data lines UART1_TXD/UART1_RXD, hardware flow control lines UART1_RTS/UART1_CTS, status lines UART1_DTR、UART1_DCD and UART1_RI. Serial port can be used for GPRS service and AT communication. It can also be used for multiplexing function. For details about multiplexing function, please refer to table 11.
Smart Machine Smart Decision 4.5.2 Serial Interfaces The following figure shows the connection between module and client (DTE). Module(DCE) Serial Port Customer(DTE) Serial Port UART1_TXD TXD UART1_RXD RXD UART1_RTS RTS UART1_CTS CTS UART1_DTR DTR UART1_DCD DCD UART1_RI RING GND GND Figure 18: Connection of the serial interfaces If the voltage of UART is 3.3V, the following reference circuits are recommended. If the voltage is 3.
Smart Machine Smart Decision If the voltage of UART is 5V, the following reference circuits are recommended: VDD_EXT Module DTE VDD 4.7K VDD_EXT 4.7K 47K RXD UART1_TXD Figure 21: TX level matching circuit VDD_EXT Module DTE VDD_EXT VDD 4.7K 4.7K 47K TXD UART1_RXD Figure 22: RX level matching circuit 4.5.3 Debug Interface SIM868 could achieve software debug function through USB interface.
Smart Machine Smart Decision Note: please reserve the USB interface or test point for the further debugging Table 11: USB_VBUS operation voltage Pin Min Typ Max Unit USB_VBUS 4.3 5.0 7.0 V 4.5.4 Software Upgrade Customer could upgrade module’s firmware through USB or UART interface. If upgrading through USB interface, it is necessary to power on SIM868 first, and then connect USB_VBUS, USB_DP, USB_DM, and GND to PC.
Smart Machine Smart Decision The behavior of the RI pin is shown in the following figure when the module is used as a receiver. RI HIGH Establish the call Hang up the call LOW Idle Ring Figure 25: UART1_RI behaviour of voice calling as a receiver HIGH RI 120ms LOW Idle Receive SMS URC Figure 26: UART1_RI behaviour of URC or receive SMS However, if the module is used as caller, the UART1_RI will remain high. Please refer to the following figure.
Smart Machine Smart Decision SIM868 internal has class-AB audio amplifier, the following table is class-AB performance: Table 14: Performance of audio amplifier Test Conditions Class-AB AMP 4.2V 8Ω THD+N=1% 0.87W 3.3V 8Ω THD+N=1% 0.53W 4.2V 8Ω THD+N=10% 1.08W 3.3V 8Ω THD+N=10% 0.65W SPK2P/2N output can directly drive 8Ω speaker. AT command “AT+CMIC” is used to adjust the input gain level of microphone. AT command “AT+SIDET” is used to set the side-tone level.
Smart Machine Smart Decision 4.7.2. Microphone Interfaces Configuration These components should be placed to microphone as close as possible MICP MICN 10pF 33pF The lines in bold type should be accorded to differential 10pF signal layout rules 33pF 10pF 33pF Module ESD ESD Electret Microphone Figure 29: Microphone reference circuit 4.7.3. Audio Electronic Characteristic Table 15: Microphone input characteristics Parameter Min Typ Max Unit Microphone biasing voltage - 1.9 2.
Smart Machine Smart Decision Conducting noise is mainly caused by the VBAT drop. If audio PA was powered by VBAT directly, then there will be some cheep noise from speaker output easily. So it is better to put big capacitors and ferrite beads near audio PA input. TDD noise has something to do with GND signal. If GND plane is not good, lots of high-frequency noises will interference microphone and speaker over bypass capacitor. So a good GND during PCB layout could avoid TDD noise. 4.8.
Smart Machine Smart Decision holder to implement SIM card detection function. AT command “AT+CSDT” is used to enable or disable SIM card detection function. For details of this AT command, please refer to document [1]. If the SIM card detection function is not used, customer can keep the SIM_DET pin open. The reference circuit of 6-pin SIM card holder is illustrated in the following figure.
Smart Machine Smart Decision 4.8.3. Design Considerations for SIM Card Holder For 8 pins SIM card holder, SIMCom recommends to use Molex 91228.Customer can visit http://www.molex.com for more information about the holder.
Smart Machine Smart Decision For 6-pin SIM card holder, SIMCom recommends to use Amphenol C707 10M006 512 .Customer can visit http://www.amphenol.com for more information about the holder.
Smart Machine Smart Decision 4.9. SD Interface SD interface can be configured as PCM interface; the following table shows the detailed multiplexing function. Table 20: SD multiplexing function Pin name Pin number Mode 0(default) Mode 1 Mode 2 Mode 3 MCCA3 46 MCCA3 DAIPCMOUT(1.8V) GPIO EINT19 MCCA2 47 MCCA2 DAICLK(1.8v) GPIO EINT18 MCCA1 48 MCCA1 DAIPCMIN(1.8v) GPIO EINT17 MCCA0 49 MCCA0 DAISYNC (1.
Smart Machine Smart Decision Pin name Pin number Mode 0(default) Mode 1 SCL 65 SCL GPIO SDA 64 SDA GPIO Note: Customer can use AT command set mode. For detail, please refer to document t[1]. 4.11. ADC Table 23: Pin definition of the ADC Pin name Pin number Description ADC 38 Analog voltage input SIM868 provides an auxiliary ADC, which can be used to measure the voltage. Customer can use AT command “AT+CADC” to read the voltage value. Note: Customer can use AT command set mode.
Smart Machine Smart Decision Reference circuit is recommended in the following figure: VBAT R Module 4.7K NETLIGHT 47K Figure 35: Reference circuit of NETLIGHT Table 27: NETLIGHT multiplexing function Pin name Pin number Mode 0(default) Mode 1 NETLIGHT 41 NETLIGHT GPIO Note: Customer can use AT command set mode. For detail, please refer to document t[1]. 4.13. Operating Status Indication The pin42 is for operating status indication of the module.
Smart Machine Smart Decision 220us 577us Transmit burst RF_SYNC Figure 36: RF_SYNC signal during transmit burst 4.14.1. RF_SYNC Multiplexing Function RF_SYNC can also be used as GPIO to indicate the RF Jamming. The RF_SYNC function and RF Jamming Detection function can be switched by AT+SJDR command. Table 30: RF_SYNC Multiplexing function Pin name Pin number Mode 0(default) Mode 1 RF_SYNC 29 RF Synchronization Signal JD（RF jamming detection） Note: About AT+SJDR, please refer to document [1].
Smart Machine Smart Decision It is recommended that the GSM antenna should be placed as far as possible. The isolations of the two antenna should be bigger than 30dB The modular connection to the antenna is made through a host’s printed board microstrip trace layout,the impendence of the microstrip trace is control in 50Ω，the series connection component in the trace is 0Ω resistors for default, the size of series connection componentcan be 0402 or 0201.
Smart Machine Smart Decision Dipole Antenna Reference PCBLayout Requirements. Dipole Antenna Reference Design PCB Mount these devices with brown mark facing up. Units: mm Line width should be designed to provide 50Ωimpedance matching characteristics. SIM868_Hardware_Design_V1.
Smart Machine Smart Decision SIM868_Hardware_Design_V1.
Smart Machine Smart Decision The RF test connector in the figure is used for the conducted RF performance test, and should be placed as close as to the module’s antenna pin. The traces impedance between components must be controlled in 50Ω.
Smart Machine Smart Decision It have according to reference trace and matching circuit testing all FCC items,and all items satisfy FCC requirements.Only the reference trace and matching circuit is certified, antenna design must refer to it, any other deviations require testing Class II applications as required by FCC.
Smart Machine Smart Decision 5. PCB Layout This section will give some guidelines on PCB layout, in order to eliminate interfere or noise. 5.1 Pin Assignment Before PCB layout, we should learn about pin assignment in order to get reasonable layout with so many external components. Following figure is the overview of pin assignment of the module. Figure 41: PIN assignment SIM868_Hardware_Design_V1.
Smart Machine Smart Decision 5.2 Principle of PCB Layout During layout, attention should be paid to the following interfaces, like Antenna, power supply, SIM card interface, audio interface, and so on. 5.2.1 Antenna Interface 5.2.2 Power Supply 5.2.3 SIM card holder has no anti-EMI component inside.
Smart Machine Smart Decision 6. Electrical, Reliability and Radio Characteristics 6.1 Absolute Maximum Ratings The absolute maximum ratings stated in following table are stress ratings under non-operating conditions. Stresses beyond any of these limits will cause permanent damage to SIM868. Table 32: Absolute maximum ratings Symbol Min Typ Max Unit VBAT - - 4.5 V Current 0 - 2.
Smart Machine Smart Decision VIH High-level input voltage VIL Low-level input voltage VOH High-level output voltage VOL Low-level output voltage 6.5 1.4 - - V 2.4 - - V - - 0.27 V 0.4 V 1.62 - - V 2.7 - - V - - 0.36 V - - 0.4 V Min Typ Max Unit - 3.0 - - 1.8 - - - 10 mA SIM_VDD Characteristics Table 36: SIM_VDD characteristics Symbol Parameter VO Output voltage IO Output current 6.
Smart Machine Smart Decision PCS1900 13.7 mA 223 234 mA mA 162 170 mA mA Data mode GPRS (1Rx,4Tx)： GSM850 EGSM900 DCS1800 PCS1900 378 414 270 308 mA mA mA mA Data mode GPRS (3Rx,2Tx)： GSM850 EGSM900 DCS1800 PCS1900 323 340 212 236 mA mA mA mA Data mode GPRS (4Rx,1Tx)： GSM850 EGSM900 DCS1800 PCS1900 217 223 153 163 mA mA mA mA Voice call (PCL=5)： GSM850 EGSM900 Voice call (PCL=0)： DCS1800 PCS1900 IMAX Peak current During Tx burst 2.
Smart Machine Smart Decision specification requirement. Table 40: GSM850 and EGSM900 conducted RF output power GSM850,EGSM900 PCL Tolerance (dB) for conditions Nominal output power (dBm) Normal Extreme 5 33 ±2 ±2.
Smart Machine Smart Decision 14 2 ±5 ±6 15 0 ±5 ±6 For the module’s output power, the following should be noted: At GSM900 and GSM850 band, the module is a class 4 device, so the module’s output power should not exceed 33dBm, and at the maximum power level, the output power tolerance should not exceed +/-2dB under normal condition and +/-2.5dB under extreme condition.
Smart Machine Smart Decision 7. Manufacturing 7.1. Top and Bottom View of SIM868 Figure 42: Top and bottom view of SIM868 7.2. Typical Solder Reflow Profile Figure 43: Typical solder reflow profile of lead-free process 7.3. The Moisture Sensitivity Level The moisture sensitivity level of SIM868 module is 3. The modules should be mounted within 168 hours after unpacking in the environmental conditions of temperature <30℃ and relative humidity of <60% (RH).
Smart Machine Smart Decision Table 44: Moisture sensitivity level and floor life Moisture Sensitivity Level (MSL) Floor Life (out of bag) at factory ambient≤30°C/60% RH or as stated 1 Unlimited at ≦30℃/85% RH 2 1 year 2a 4 weeks 3 168 hours 4 72 hours 5 48 hours 5a 24 hours 6 Mandatory bake before use. After bake, it must be reflowed within the time limit specified on the label. NOTES: 1.
Smart Machine Smart Decision 8. Appendix I. Related Documents Table 46: Related documents SN Document name [1] SIM800_Series_AT_Command_ Manual [2] SIM800 Series Port Application Note_V1 02.doc [3] ITU-T Draft new recommendation V.25ter： Serial asynchronous automatic dialing and control [4] GSM 07.07： Digital cellular telecommunications (Phase 2+); AT command set for GSM Mobile Equipment (ME) [5] GSM 07.10： Support GSM 07.10 multiplexing protocol GSM 07.
Smart Machine Smart Decision II.
Smart Machine Smart Decision PAP Password Authentication Protocol PBCCH Packet Broadcast Control Channel PCB Printed Circuit Board PCL Power Control Level PCS Personal Communication System, also referred to as GSM 1900 PDU Protocol Data Unit PPP Point-to-point protocol RF Radio Frequency RMS Root Mean Square (value) RX Receive Direction SIM Subscriber Identification Module SMS Short Message Service TE Terminal Equipment, also referred to as DTE TX Transmit Direction SINAD Signa
Smart Machine Smart Decision IV. Safety Caution Table 49: Safety caution Marks Requirements When in a hospital or other health care facility, observe the restrictions about the use of mobiles. 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 is switched off.
Smart Machine Smart Decision Contact us: Shanghai SIMCom Wireless Solutions Co.,Ltd. Address: Building A, SIM Technology Building, No. 633, Jinzhong Road, Shanghai, P. R. China 200335 Tel: +86 21 3252 3300 Fax: +86 21 3252 3020 URL: www.sim.com/wm SIM868_Hardware_Design_V1.
