SimCom SIM548C HD V1.01 Hardware Design page 4

SIM548C Hardware Design
3.11 SIM interface....................................................................................................................53
3.11.1 SIM card application ..............................................................................................53
3.11.2 Design considerations for SIM card holder ............................................................55
3.12 LCD interface...................................................................................................................57
3.13 ADC .................................................................................................................................58
3.14 General purpose input & output(GPIO) ...........................................................................58
3.15 Behaviors of the RI line (serial port1 interface only).......................................................58
3.16 Network status indication.................................................................................................60
3.17 Buzzer ..............................................................................................................................60
4 GPS application interface.............................................................................................................62
4.1 Theory of operation............................................................................................................62
4.2 Technical data.....................................................................................................................63
4.3 Pin description....................................................................................................................64
4.4 Turn on the GPS part..........................................................................................................66
4.5 The theory of the GPS RTC circuit ....................................................................................67
4.6 The theory of the RESET Circuit .......................................................................................68
4.7 GPS operation modes .........................................................................................................69
4.8 Serial interface of the GPS part..........................................................................................69
4.9 Start-up procedure ..............................................................................................................70
4.9.1 Coldstart ...................................................................................................................70
4.9.2 Warmstart .................................................................................................................70
4.9.3 Hotstart .....................................................................................................................71
5 Antenna interface .........................................................................................................................72
5.1 GSM Antenna.....................................................................................................................72
5.1.1 GSM Antenna connector ..........................................................................................72
5.1.2 GSM Antenna pad ....................................................................................................72
5.1.3 Module RF output power..........................................................................................74
5.1.4 Module RF receive sensitivity..................................................................................74
5.1.5 Module operating frequencies ..................................................................................74
5.2 GPS Antenna ......................................................................................................................74
5.2.1 GPS Antenna Connection.........................................................................................74
5.2.2 GPS Antenna Choice Consideration ........................................................................75
6 Electrical, reliability and radio characteristics .............................................................................77
6.1 Absolute maximum ratings.................................................................................................77
6.2 Operating temperatures ......................................................................................................77
6.3 Power supply rating............................................................................................................78
6.4 Current consumption ..........................................................................................................79
6.4.1 The current consumption of the GSM part...............................................................79
6.4.2 The current consumption of the GPS part ................................................................80
6.5 Electrostatic discharge........................................................................................................83
7 Mechanics ....................................................................................................................................85
7.1 Mechanical dimensions ......................................................................................................85
7.2 Mounting the module onto the application platform..........................................................86
7.3 Board-to-board connector ..................................................................................................86
SIM548C_HD_V1.01
4
09.05.2008