SIM900 Hardware Design
3.12 Keypad Interface .......................................................................................................................................42
3.13 ADC ..........................................................................................................................................................44
3.14 Behaviors of the RI ...................................................................................................................................44
3.15 Network Status Indication.........................................................................................................................45
3.16 General Purpose Input Output (GPIO)......................................................................................................46
3.17 External Reset ...........................................................................................................................................47
3.18 PWM .........................................................................................................................................................47
3.19 I2C Bus......................................................................................................................................................47
4 Antenna Interface ..................................................................................................................................................48
4.1 Module RF Output Power ...........................................................................................................................48
4.2 Module RF Receive Sensitivity...................................................................................................................48
4.3 Module Operating Frequencies ...................................................................................................................49
5 Electrical, Reliability and Radio Characteristics...................................................................................................49
5.1 Absolute Maximum Ratings........................................................................................................................49
5.2 Operating Temperatures..............................................................................................................................49
5.3 Power Supply Ratings .................................................................................................................................50
5.4 Current Consumption(VBAT = 3.8V).........................................................................................................51
5.5 Electro-Static Discharge..............................................................................................................................52
6 Mechanics .............................................................................................................................................................52
6.1 Mechanical Dimensions of SIM900............................................................................................................52
6.2 Top and Bottom View of the SIM900 .........................................................................................................55
6.3 PIN Assignment of SIM900........................................................................................................................56
6.4 The Ramp-Soak-Spike Reflow Profile of SIM900 .....................................................................................58
SIM900_HD_V1.05 06.23.2010
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