Table Of Contents; Contents - SimCom SIM548C HD V1.01 Hardware Design

SIM548C Hardware Design

Contents

Contents ............................................................................................................................................3
Version History.................................................................................................................................9
Scope of the document......................................................................................................................9
1 Introduction..................................................................................................................................10
1.1 Related documents .............................................................................................................10
1.2 Terms and abbreviations ....................................................................................................11
2 Overview......................................................................................................................................14
2.1 Key features .......................................................................................................................15
2.2 Functional diagram.............................................................................................................17
2.3 Evaluation board ................................................................................................................18
3 GSM application interface ...........................................................................................................19
3.1 Pin description....................................................................................................................19
3.2 Operating modes ................................................................................................................21
3.3 Power supply......................................................................................................................23
3.3.1 Power supply pins on the board-to-board connector ................................................25
3.3.2 Minimizing power losses..........................................................................................25
3.3.3 Monitoring power supply .........................................................................................25
3.4 Power up and down scenarios ............................................................................................25
3.4.1 Turn on the GSM part...............................................................................................25
3.4.2 Turn off the GSM part..............................................................................................29
3.4.3 Restart the GSM part using the PWRKEY pin.........................................................32
3.5 Charging interface ..............................................................................................................32
3.5.1 Battery pack characteristics......................................................................................33
3.5.2 Recommended battery pack .....................................................................................34
3.5.3 Implemented charging technique..............................................................................35
3.5.4 Operating modes during charging ............................................................................36
3.5.5 Charger requirements ...............................................................................................38
3.6 Power saving ......................................................................................................................38
3.6.1 Minimum functionality mode...................................................................................38
3.6.2 SLEEP mode (slow clock mode)..............................................................................39
3.6.3 Wake up the GSM part from SLEEP mode..............................................................39
3.7 Summary of state transitions (except SLEEP mode) .........................................................40
3.8 RTC backup........................................................................................................................41
3.9 GSM Serial interface..........................................................................................................44
3.9.1 Function of serial port & debug port supporting ......................................................46
3.9.2 Software upgrade and software debug......................................................................47
3.10 Audio interfaces ...............................................................................................................49
3.10.1 Speaker interface configuration..............................................................................50
3.10.2 Microphone interfaces configuration......................................................................51
3.10.3 Earphone interface configuration ...........................................................................52
3.10.4 Referenced electronic characteristic.......................................................................52
SIM548C_HD_V1.01
3
09.05.2008