Sim800 hardware design v1.05

Smart Machine Smart Decision
SIM800_Hardware Design_V1.05 7 2014-03-25
Figure Index
FIGURE 1: SIM800 FUNCTIONAL DIAGRAM ........................................................................................................... 13
FIGURE 2: SIM800 PIN OUT DIAGRAM (TOP VIEW) ............................................................................................... 14
FIGURE 3: DIMENSIONS OF SIM800 (UNIT: MM).................................................................................................... 18
FIGURE 4: RECOMMENDED PCB FOOTPRINT OUTLINE (UNIT: MM) ................................................................ 19
FIGURE 5: REFERENCE CIRCUIT OF THE VBAT INPUT......................................................................................... 20
FIGURE 6: REFERENCE CIRCUIT OF THE POWER SUPPLY .................................................................................. 20
FIGURE 7: REFERENCE CIRCUIT OF THE DC-DC POWER SUPPLY..................................................................... 21
FIGURE 8: VBAT VOLTAGE DROP DURING TRANSMIT BURST........................................................................... 21
FIGURE 9: THE MINIMAL VBAT VOLTAGE REQUIREMENT AT VBAT DROP .................................................... 22
FIGURE 10: POWER ON/DOWN MODULE USING TRANSISTOR .......................................................................... 22
FIGURE 11: POWER ON/DOWN MODULE USING BUTTON................................................................................... 23
FIGURE 12: TIMING OF POWER ON MODULE......................................................................................................... 23
FIGURE 13: TIMING OF POWER DOWN SIM800 BY PWRKEY .............................................................................. 24
FIGURE 14: RESET CIRCUIT........................................................................................................................................ 26
FIGURE 15: RESET TIMING SEQUENCE.................................................................................................................... 26
FIGURE 16: RTC SUPPLY FROM CAPACITOR........................................................................................................... 28
FIGURE 17: RTC SUPPLY FROM NON-CHARGEABLE BATTERY ......................................................................... 28
FIGURE 18: RTC SUPPLY FROM RECHARGEABLE BATTERY .............................................................................. 28
FIGURE 19: CONNECTION OF THE SERIAL PORT................................................................................................... 30
FIGURE 20: LEVEL CONVERTING BY RESISTOR.................................................................................................... 31
FIGURE 21: ISOLATION CIRCUIT BY DIODES ......................................................................................................... 31
FIGURE 22: TX LEVEL CONVERTING BY TRANSISTOR........................................................................................ 31
FIGURE 23: RX LEVEL CONVERTING BY TRANSISTOR ....................................................................................... 32
FIGURE 24: USB REFERENCE CIRCUIT .................................................................................................................... 32
FIGURE 25: CONNECTION FOR SOFTWARE UPGRADING.................................................................................... 33
FIGURE 26: RI BEHAVIOUR OF VOICE CALLING AS A RECEIVER...................................................................... 34
FIGURE 27: RI BEHAVIOUR OF DATA CALLING AS A RECEIVER........................................................................ 34
FIGURE 28: RI BEHAVIOUR OF URC OR RECEIVE SMS ........................................................................................ 35
FIGURE 29: RI BEHAVIOUR AS A CALLER ............................................................................................................... 35
FIGURE 30: SPEAKER REFERENCE CIRCUIT .......................................................................................................... 36
FIGURE 31: MICROPHONE REFERENCE CIRCUIT.................................................................................................. 36
FIGURE 32: REFERENCE CIRCUIT OF THE 8-PIN SIM CARD HOLDER............................................................... 38
FIGURE 33: REFERENCE CIRCUIT OF THE 6-PIN SIM CARD HOLDER............................................................... 39
FIGURE 34: MOLEX 91228 SIM CARD HOLDER ...................................................................................................... 40
FIGURE 35: AMPHENOL C707 10M006 5122 SIM CARD HOLDER......................................................................... 41
FIGURE 36: PCM REFERENCE CIRCUIT.................................................................................................................... 43
FIGURE 37: LCD REFERENCE CIRCUIT .................................................................................................................... 43
FIGURE 38: SD REFERENCE CIRCUIT....................................................................................................................... 44
FIGURE 39: TRADITIONAL KEYPAD REFERENCE CIRCUIT................................................................................. 44
FIGURE 40: EXTENDED KEYPAD REFERENCE CIRCUIT ...................................................................................... 45
FIGURE 41: ENHANCE THE ESD PERFORMANCE OF KEYPAD CIRCUIT........................................................... 45
FIGURE 42: KEYPAD DETECTED ............................................................................................................................... 46
FIGURE 43: REFERENCE CIRCUIT OF PWM DRIVE BUZZER ............................................................................... 49
FIGURE 44: REFERENCE CIRCUIT OF NETLIGHT .................................................................................................. 50
FIGURE 45: KPLED DRIVER REFERENCE CIRCUIT................................................................................................ 50
FIGURE 46: RF_SYNC SIGNAL DURING TRANSMIT BURST ................................................................................ 51