Quectel M20

M20 Hardware Design
Figure Index
FIGURE 1: MODULE FUNCTIONAL DIAGRAM .............................................................................17
FIGURE 2: REFERENCE BYPASS CAPACITORS FOR THE VBAT INPUT....................................24
FIGURE 3: REFERENCE CIRCUIT OF THE SOURCE POWER SUPPLY INPUT...........................24
FIGURE 4: RIPPLE IN SUPPLY VOLTAGE DURING TRANSMITTING BURST...........................25
FIGURE 5: TURN ON THE MODULE BY USING DRIVING CIRCUIT ..........................................27
FIGURE 6: TURN ON THE MODULE BY USING BUTTON............................................................27
FIGURE 7: TIMING OF TURN ON THE MODULE ...........................................................................28
FIGURE 8: TIMING OF TURN OFF THE MODULE .........................................................................30
FIGURE 9: REFERENCE CIRCUIT FOR EMERG_OFF BY USING DRIVING CIRCUIT..............31
FIGURE 10: REFERENCE CIRCUIT FOR EMERG_OFF BY USING BUTTON..............................31
FIGURE 11: TIMING OF RESTART THE SYSTEM ...........................................................................32
FIGURE 12: TIMING OF RESTART THE SYSTEM AFTER EMERGENCY SHUTDOWN ............32
FIGURE 13: CHARGING CIRCUIT CONNECTION..........................................................................33
FIGURE 14: REFERENCE EXTERNAL BATTERY CHARGING CIRCUIT.....................................34
FIGURE 15: NORMAL CHARGING PROCESS DIAGRAM .............................................................38
FIGURE 16: RTC SUPPLY FROM NON-CHARGEABLE BATTERY ...............................................42
FIGURE 17: RTC SUPPLY FROM RECHARGEABLE BATTERY ....................................................42
FIGURE 18: RTC SUPPLY FROM CAPACITOR ................................................................................42
FIGURE 19: SEIKO XH414H-IV01E CHARGING CHARACTERISTIC ..........................................43
FIGURE 20: CONNECTION OF SERIAL INTERFACES ...................................................................44
FIGURE 21: CONNECTION OF SOFTWARE UPGRADE .................................................................46
FIGURE 22: CONNECTION OF SOFTWARE DEBUGGING ............................................................47
FIGURE 23: RS-232 LEVEL CONVERTER CIRCUIT .......................................................................47
FIGURE 24: ELECTRET MICROPHONE INTERFACE CONFIGURATION OF AIN1....................49
FIGURE 25: ELECTRET MICROPHONE INTERFACE CONFIGURATION OF AIN2....................50
FIGURE 26: SIGNAL SOURCE INTERFACE CONFIGURATION OF AIN1/AIN2..........................50
FIGURE 27: SPEAKER INTERFACE CONFIGURATION OF AOUT1 .............................................51
FIGURE 28: SPEAKER INTERFACE WITH AMPLIFIER IN AOUT1 ..............................................51
FIGURE 29: SPEAKER INTERFACE CONFIGURATION OF AOUT2 .............................................52
FIGURE 30: SPEAKER INTERFACE WITH AMPLIFIER IN AOUT2 ..............................................52
FIGURE 31: EARPHONE INTERFACE CONFIGURATION..............................................................53
FIGURE 32: TIMING DIAGRAM OF DAI INTERFACE....................................................................55
FIGURE 33: REFERENCE CIRCUIT OF USING 8-PIN SIM CARD SOCKET.................................56
FIGURE 34: REFERENCE CIRCUIT OF USING 6-PIN SIM CARD SOCKET.................................57
FIGURE 35: AMPHENOL C707 10M006 512 2 SIM CARD HOLDER..............................................57
FIGURE 36: MOLEX 91228 SIM CARD HOLDER ............................................................................58
FIGURE 37: RI0 BEHAVIOUR OF VOICE CALLING AS A RECEIVER .........................................60
FIGURE 38: RI0 BEHAVIOUR OF DATA CALLING AS A RECEIVER ...........................................60
FIGURE 39: RI0 BEHAVIOUR OF DATA CALLING AS A CALLER ...............................................60
FIGURE 40: RI0 BEHAVIOUR OF URC OR SMS RECEIVED .........................................................61
FIGURE 41: REFERENCE CIRCUIT OF NETLIGHT ........................................................................61
M20_HD_V1.01 - 6 -
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