User's Manual

GSM/GPRS/GNSS Module Series
MC20 Hardware Design
MC20_Hardware_Design Confidential / Released 8 / 95
Figure Index
FIGURE 1: MODULE FUNCTIONAL DIAGRAM ..................................................................................... 18
FIGURE 2: PIN ASSIGNMENT ............................................................................................................... 20
FIGURE 3: ALL-IN-ONE SOLUTION SCHEMATIC DIAGRAM ............................................................... 26
FIGURE 4: STAND-ALONE SOLUTION SCHEMATIC DIAGRAM .......................................................... 26
FIGURE 5: VOLTAGE RIPPLE DURING TRANSMITTING (GSM PART) ............................................... 28
FIGURE 6: REFERENCE CIRCUIT FOR THE VBAT INPUT (GSM PART) ............................................ 29
FIGURE 7: REFERENCE CIRCUIT FOR THE GNSS_VCC INPUT ....................................................... 29
FIGURE 8: REFERENCE CIRCUIT FOR POWER SUPPLY OF THE GSM PART ................................. 30
FIGURE 9: REFERENCE CIRCUIT DESIGN FOR GNSS PART ............................................................ 31
FIGURE 10: INTERNAL GNSS’S BACKUP DOMAIN POWER CONSTRUCTION ................................. 32
FIGURE 11: TURN ON THE MODULE WITH AN OPEN-COLLECTOR DRIVER ................................... 38
FIGURE 12: TURN ON THE MODULE WITH A BUTTON ...................................................................... 39
FIGURE 13: TURN-ON TIMING .............................................................................................................. 39
FIGURE 14: TURN-OFF TIMING BY USING THE PWRKEY PIN ........................................................... 41
FIGURE 15: TURN-OFF TIMING OF GNSS PART BY USING AT COMMAND ...................................... 42
FIGURE 16: REFERENCE DESIGN FOR FULL-FUNCTION UART ...................................................... 47
FIGURE 17: REFERENCE DESIGN FOR UART PORT (THREE LINE CONNECTION) ........................ 47
FIGURE 18: REFERENCE DESIGN FOR UART PORT WITH HARDWARE FLOW CONTROL............ 48
FIGURE 19: REFERENCE DESIGN FOR FIRMWARE UPGRADE ....................................................... 48
FIGURE 20: REFERENCE DESIGN FOR DEBUG PORT ...................................................................... 49
FIGURE 21: AUXILIARY AND GNSS UART PORT CONNECTION IN ALL-IN-ONE SOLUTION ........... 50
FIGURE 22: AUXILIARY AND GNSS UART PORT CONNECTION IN STAND-ALONE SOLUTION ...... 51
FIGURE 23: LEVEL MATCH DESIGN FOR 3.3V SYSTEM .................................................................... 51

FIGURE 24: SKETCH MAP FOR RS-232 INTERFACE MATCH ............................................................ 52
FIGURE 25: REFERENCE DESIGN FOR AIN ........................................................................................ 54
FIGURE 26: HANDSET INTERFACE DESIGN FOR AOUT1 .................................................................. 55
FIGURE 27: SPEAKER INTERFACE DESIGN WITH AN AMPLIFIER FOR AOUT1 .............................. 55
FIGURE 28: EARPHONE INTERFACE DESIGN .................................................................................... 56
FIGURE 29: LOUD SPEAKER INTERFACE DESIGN ............................................................................ 56
FIGURE 30: REFERENCE CIRCUIT FOR SIM1 INTERFACE WITH AN 8-PIN SIM CARD HOLDER ... 59
FIGURE 31: REFERENCE CIRCUIT FOR SIM1 INTERFACE WITH A 6-PIN SIM CARD HOLDER ...... 59
FIGURE 32: REFERENCE CIRCUIT FOR SIM2 INTERFACE WITH A 6-PIN SIM CARD HOLDER ...... 60
FIGURE 33: RI BEHAVIOR AS A RECEIVER WHEN VOICE CALLING ................................................. 62
FIGURE 34: RI BEHAVIOR AS A CALLER.............................................................................................. 62
FIGURE 35: RI BEHAVIOR WHEN URC OR SMS RECEIVED .............................................................. 62
FIGURE 36: REFERENCE DESIGN FOR NETLIGHT ............................................................................ 63
FIGURE 37: REFERENCE DESIGN FOR GSM ANTENNA ................................................................... 66
FIGURE 38: RF SOLDERING SAMPLE ................................................................................................. 69
FIGURE 39: REFERENCE DESIGN WITH ACTIVE ANTENNA ............................................................. 70
FIGURE 40: REFERENCE DESIGN WITH PASSIVE ANTENNA ........................................................... 71
FIGURE 41: REFERENCE DESIGN FOR BLUETOOTH ANTENNA ...................................................... 72