SimCom SIM808

Smart Machine Smart Decision
SIM808_Hardware Design_V1.00 2014.03.27
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4.9.1 Antenna Interface................................................................................................................................ 39
4.10 SIM Card Interface ................................................................................................................................. 39
4.10.1 SIM Card Application...................................................................................................................... 40
4.10.2 SIM Card Design Consideration...................................................................................................... 41
4.10.3 Design Considerations for SIM Card Holder................................................................................... 41
4.11 PCM Interface ........................................................................................................................................ 43
4.11.1 PCM Multiplex Function................................................................................................................. 43
4.11.2 PCM Interface.................................................................................................................................. 44
4.11.3 LCD Display/SPI Interface.............................................................................................................. 44
4.11.4 SD Card Interface ............................................................................................................................ 45
4.12 Keypad Interface .................................................................................................................................... 45
4.13 I2C BUS ................................................................................................................................................. 47
4.13.1 General Purpose Input/Output (GPIO) ............................................................................................ 48
4.14 ADC........................................................................................................................................................ 48
4.15 PWM ...................................................................................................................................................... 49
4.16 Network Status Indication ...................................................................................................................... 50
4.17 Operating Status Indication .................................................................................................................... 50
4.18 RF Synchronization Signal..................................................................................................................... 51
4.19 Antenna Interface ................................................................................................................................... 51
5 GPS Application Interface ............................................................................................................................. 52
5.1 GPS Operating Modes............................................................................................................................ 52
5.2 GPS Power on/down Scenarios .............................................................................................................. 53
5.2.1 Power on GPS engine.......................................................................................................................... 53
5.2.2 Power down GPS engine..................................................................................................................... 53
5.3 GPS Antenna Interface ........................................................................................................................... 53
5.3.1 GPS Antenna Interface........................................................................................................................ 53
5.3.2 GPS Antenna Choice Consideration ................................................................................................... 53
6 Electrical, Reliability and Radio Characteristics......................................................................................... 54
6.1 Absolute Maximum Ratings................................................................................................................... 54
6.2 Recommended Operating Conditions..................................................................................................... 55
6.3 Digital Interface Characteristics ............................................................................................................. 55
6.4 SIM Card Interface Characteristics ........................................................................................................ 55
6.5 SIM_VDD Characteristics...................................................................................................................... 56
6.6 VDD_EXT Characteristics ..................................................................................................................... 56
6.7 VRTC Characteristics ............................................................................................................................. 56
6.8 Current Consumption (VBAT = 4V, GPS engine is powered down)...................................................... 56
6.9 Electro-Static Discharge ......................................................................................................................... 57
6.10 Radio Characteristics.............................................................................................................................. 58
6.10.1 Module RF Output Power................................................................................................................ 58
6.10.2 Module RF Receive Sensitivity ....................................................................................................... 59
6.10.3 Module Operating Frequencies........................................................................................................ 60
7 Manufacturing ................................................................................................................................................ 61
7.1 Top and Bottom View of SIM808........................................................................................................... 61
7.2 Typical Solder Reflow Profile ................................................................................................................ 61
7.3 The Moisture Sensitivity Level .............................................................................................................. 62
7.4 Baking Requirements ............................................................................................................................. 62
Appendix ................................................................................................................................................................ 63