SimCom SIM900D Hardware Design page 6

SIM900D Hardware Design
Figure Index
FIGURE1: SIM900D FUNCTIONAL DIAGRAM ......................................................................................................... 16
FIGURE2: TOP VIEW OF SIM900D EVB ..................................................................................................................... 17
FIGURE3: REFERENCE CIRCUIT OF THE VBAT INPUT ......................................................................................... 22
FIGURE4: REFERENCE CIRCUIT OF THE SOURCE POWER SUPPLY INPUT...................................................... 23
FIGURE5: VBAT VOLTAGE DROP DURING TRANSMIT BURST ........................................................................... 23
FIGURE6: THE MINIMAL VBAT VOLTAGE AT VBAT DROP................................................................................... 24
FIGURE7: TURN ON SIM900D USING DRIVING CIRCUIT ..................................................................................... 25
FIGURE8: TURN ON SIM900D USING BUTTON ....................................................................................................... 25
FIGURE9: TIMING OF TURN ON SYSTEM USING PWRKEY ................................................................................. 25
FIGURE10: TIMING OF TURN OFF SYSTEM USING PWRKEY.............................................................................. 27
FIGURE11: TIMING OF RESTART SIM900D .............................................................................................................. 28
FIGURE12: SIM900D WITH BATTERY CHARGER AND PACK CONNECTION..................................................... 29
FIGURE13: CHARGE STATE TRANSITION................................................................................................................ 32
FIGURE14: RTC SUPPLY FROM NON-CHARGEABLE BATTERY .......................................................................... 35
FIGURE15: RTC SUPPLY FROM RECHARGEABLE BATTERY ............................................................................... 35
FIGURE16: RTC SUPPLY FROM CAPACITOR ........................................................................................................... 35
FIGURE17: SEIKO XH414H-IV01E CHARGE CHARACTERISTICS........................................................................ 36
FIGURE18: CONNECTION OF THE SERIAL INTERFACES ..................................................................................... 37
FIGURE19: CONNECTION OF SOFTWARE UPGRADE AND SOFTWARE DEBUG .............................................. 39
FIGURE20: RS232 LEVEL CONVERTER CIRCUIT.................................................................................................... 39
FIGURE21: SPEAKER INTERFACE CONFIGURATION ............................................................................................ 41
FIGURE22: SPEAKER INTERFACE WITH AMPLIFIER CONFIGURATION ........................................................... 41
FIGURE23: MICROPHONE INTERFACE CONFIGURATION.................................................................................... 42
FIGURE24: EARPHONE INTERFACE CONFIGURATION......................................................................................... 42
FIGURE25: REFERENCE CIRCUIT OF THE 8-PIN SIM CARD HOLDER ............................................................... 45
FIGURE26: REFERENCE CIRCUIT OF THE 6-PIN SIM CARD HOLDER ............................................................... 45
FIGURE27: AMPHENOL C707 10M006 512 2 SIM CARD HOLDER......................................................................... 46
FIGURE28: MOLEX 91228 SIM CARD HOLDER ....................................................................................................... 47
FIGURE29: RI BEHAVIOUR OF VOICE CALLING AS A RECEIVER ...................................................................... 49
FIGURE30: RI BEHAVIOUR OF DATA CALLING AS A RECEIVER ........................................................................ 49
FIGURE31: RI BEHAVIOUR OF URC OR RECEIVE SMS ......................................................................................... 50
FIGURE32: RI BEHAVIOUR AS A CALLER ................................................................................................................ 50
FIGURE33: REFERENCE CIRCUIT OF NETLIGHT ................................................................................................... 51
FIGURE34: SIM900D TOP MECHANICAL DIMENSIONS......................................................................................... 58
FIGURE35: SIM900D BOTTOM MECHANICAL DIMENSIONS ............................................................................... 58
FIGURE36: SIM900D SIDE MECHANICAL DIMENSIONS ....................................................................................... 59
FIGURE37: RECOMMENDED PCB DECAL (UNIT: MM).......................................................................................... 59
FIGURE38: TOP AND BOTTOM VIEW OF THE SIM900D ........................................................................................ 60
FIGURE39: SIM900D PIN OUT DIAGRAM (TOP VIEW) ........................................................................................... 60
FIGURE40: THE RAMP-SOAK-SPIKE REFLOW PROFILE OF SIM900D................................................................ 62
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SIM900D_Hardware Design_V1.04 2010.10.09