Smart Machine Smart Decision
SIM800C_Hardware_Design_V1.02
7
2015-4-27
Figure Index
FIGURE 1: SIM800C FUNCTIONAL DIAGRAM......................................................................................................... 12
FIGURE 2: PIN OUT DIAGRAM (TOP VIEW) ............................................................................................................. 13
FIGURE 3: DIMENSIONS OF SIM800C (UNIT: MM) ................................................................................................. 15
FIGURE 4: RECOMMENDED PCB FOOTPRINT OUTLINE (UNIT: MM) ................................................................ 16
FIGURE 5: REFERENCE CIRCUIT OF THE VBAT INPUT......................................................................................... 17
FIGURE 6: REFERENCE CIRCUIT OF THE LDO POWER SUPPLY ......................................................................... 17
FIGURE 7: REFERENCE CIRCUIT OF THE DC-DC POWER SUPPLY..................................................................... 18
FIGURE 8: VBAT VOLTAGE DROP DURING TRANSMIT BURST........................................................................... 18
FIGURE 9: THE MINIMAL VBAT VOLTAGE REQUIREMENT AT VBAT DROP .................................................... 18
FIGURE 10: POWERED ON/DOWN MODULE USING TRANSISTOR..................................................................... 19
FIGURE 11: POWERED ON/DOWN MODULE USING BUTTON ............................................................................. 19
FIGURE 12: TIMING OF POWER ON MODULE......................................................................................................... 19
FIGURE 13: TIMING OF POWER OFF SIM800C BY PWRKEY ................................................................................ 20
FIGURE 14: TIMING OF RESTART SIM800C.............................................................................................................. 22
FIGURE 15: RTC SUPPLY FROM CAPACITOR........................................................................................................... 23
FIGURE 16: RTC SUPPLY FROM NON-CHARGEABLE BATTERY ......................................................................... 24
FIGURE 17: RTC SUPPLY FROM RECHARGEABLE BATTERY .............................................................................. 24
FIGURE 18: CONNECTION OF THE SERIAL INTERFACES..................................................................................... 26
FIGURE 19: RESISTOR MATCHING CIRCUIT ........................................................................................................... 26
FIGURE 20 : DIODE ISOLATION CIRCUIT................................................................................................................. 26
FIGURE 21: TX LEVEL MATCHING CIRCUIT ........................................................................................................... 27
FIGURE 22: RX LEVEL MATCHING CIRCUIT........................................................................................................... 27
FIGURE 23: USB REFERENCE CIRCUIT .................................................................................................................... 27
FIGURE 24: CONNECTION FOR SOFTWARE UPGRADING AND DEBUGGING.................................................. 28
FIGURE 25: UART1_RI BEHAVIOUR OF VOICE CALLING AS A RECEIVER ....................................................... 29
FIGURE 26: UART1_RI BEHAVIOUR OF URC OR RECEIVE SMS.......................................................................... 29
FIGURE 27: UART1_RI BEHAVIOUR AS A CALLER................................................................................................. 29
FIGURE 28: SPEAKER REFERENCE CIRCUIT .......................................................................................................... 30
FIGURE 29: MICROPHONE REFERENCE CIRCUIT.................................................................................................. 30
FIGURE 30: REFERENCE CIRCUIT OF THE 8-PIN SIM CARD HOLDER............................................................... 32
FIGURE 31: REFERENCE CIRCUIT OF THE 6-PIN SIM CARD HOLDER............................................................... 32
FIGURE 32: MOLEX 91228 SIM CARD HOLDER ...................................................................................................... 33
FIGURE 33: AMPHENOL C707 10M006 512 SIM CARD HOLDER........................................................................... 34
FIGURE 34: REFERENCE CIRCUIT OF NETLIGHT .................................................................................................. 35
FIGURE 35: RF_SYNC SIGNAL DURING TRANSMIT BURST ................................................................................ 36
FIGURE 36: GSM ANTENNA MATCHING CIRCUIT ................................................................................................. 37
FIGURE 37: GSM ANTENNA MATCHING CIRCUIT WITHOUT RF CONNECTOR ............................................... 37
FIGURE 38: BLUETOOTH ANTENNA MATCHING CIRCUIT .................................................................................. 38
FIGURE 39: PIN ASSIGNMENT.................................................................................................................................... 39
FIGURE 40: TOP AND BOTTOM VIEW OF SIM800C ................................................................................................ 46
FIGURE 41: TYPICAL SOLDER REFLOW PROFILE OF LEAD-FREE PROCESSES.............................................. 46
