
Smart Machine Smart Decision
SIM800H _Hardware Design_V2.03 8 2016-10-10
Figure Index
FIGURE 1: SIM800H FUNCTIONAL DIAGRAM......................................................................................................... 14
FIGURE 2: PIN ASSIGNMENT (TOP VIEW)................................................................................................................ 15
FIGURE 3: DIMENSIONS OF SIM800H (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 LDO 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: POWERED ON/OFF MODULE USING TRANSISTOR .......................................................................... 22
FIGURE 11: POWERED ON/OFF MODULE USING BUTTON .................................................................................. 22
FIGURE 12: TIMING OF POWER ON MODULE......................................................................................................... 23
FIGURE 13: TIMING OF POWER DOWN SIM800H BY PWRKEY ........................................................................... 23
FIGURE 14:TIMING OF RESTART SIM800H .............................................................................................................. 24
FIGURE 15: RESET CIRCUIT........................................................................................................................................ 25
FIGURE 16: RESET TIMING SEQUENCE.................................................................................................................... 25
FIGURE 17: RTC SUPPLY FROM CAPACITOR........................................................................................................... 27
FIGURE 18: RTC SUPPLY FROM NON-CHARGEABLE BATTERY.......................................................................... 27
FIGURE 19: RTC SUPPLY FROM RECHARGEABLE BATTERY .............................................................................. 27
FIGURE 20: CONNECTION OF THE SERIAL INTERFACES ..................................................................................... 29
FIGURE 21: RESISTOR MATCHING CIRCUIT ........................................................................................................... 30
FIGURE 22: DIODE ISOLATION CIRCUIT.................................................................................................................. 30
FIGURE 23: TX LEVEL MATCHING CIRCUIT ........................................................................................................... 30
FIGURE 24: RX LEVEL MATCHING CIRCUIT ........................................................................................................... 31
FIGURE 25: USB REFERENCE CIRCUIT .................................................................................................................... 31
FIGURE 26: CONNECTION FOR SOFTWARE UPGRADING AND DEBUGGING .................................................. 32
FIGURE 27: RI BEHAVIOUR OF VOICE CALLING AS A RECEIVER...................................................................... 33
FIGURE 28: RI BEHAVIOUR OF URC OR RECEIVE SMS ........................................................................................ 33
FIGURE 29: RI BEHAVIOUR AS A CALLER ............................................................................................................... 33
FIGURE 30: SPEAKER REFERENCE CIRCUIT .......................................................................................................... 34
FIGURE 31: SPEAKER WITH AMPLIFIER REFERENCE CIRCUIT ......................................................................... 35
FIGURE 32: REFERENCE CIRCUIT OF THE 8-PIN SIM CARD HOLDER............................................................... 36
FIGURE 33: REFERENCE CIRCUIT OF THE 6-PIN SIM CARD HOLDER............................................................... 37
FIGURE 34: MOLEX 91228 SIM CARD HOLDER....................................................................................................... 38
FIGURE 35: AMPHENOL C707 10M006 512 SIM CARD HOLDER........................................................................... 39
FIGURE 36: PCM REFERENCE CIRCUIT.................................................................................................................... 40
FIGURE 37: 25 KEYS REFERENCE CIRCUIT............................................................................................................. 41
FIGURE 38: 50 KEYS REFERENCE CIRCUIT............................................................................................................. 41
FIGURE 39: KEYPAD REFERENCE CIRCUIT ............................................................................................................ 42
FIGURE 40: KEYPAD DETECTED ............................................................................................................................... 42
FIGURE 41: GPIO TIMING SEQUENCES .................................................................................................................... 43
FIGURE 42: REFERENCE CIRCUIT OF PWM DRIVER BUZZER ............................................................................ 44
FIGURE 43: REFERENCE CIRCUIT OF NETLIGHT................................................................................................... 45
FIGURE 44: LED DRIVER REFERENCE CIRCUIT..................................................................................................... 46
FIGURE 45: RF_SYNC SIGNAL DURING TRANSMIT BURST ................................................................................ 47
FIGURE 46: GSM ANTENNA MATCHING CIRCUIT.................................................................................................. 47