SIM900 Hardware Design
Parameter Min Typ Max Unit
Working Voltage 1.2 1.5 2.0 V
Working Current 200 500 uA
External Microphone Load Resistance 1.2 2.2 k Ohms
Internal biasing DC Characteristics 2.5 V
THD <1% at
F=1KHz; pre-amp
gain = 20 dB;
PGA gain = 14 dB
15.9 mVrms Differential input
voltage
THD <5% at
F=1KHz;pre-amp
gain = 0 dB; PGA
gain = 0 dB
740 mVrms
Table 11: Audio Output Characteristics
Parameter Conditions Min Typ Max Unit
RL=32 Ohm
THD=0.1%
- 91 - mW
RL=32 Ohm
THD=1%
- 96 - mW
Output swing
Voltage(single)
1.1V Vpp
Output swing
Voltage(differentia
l)
2.2 Vpp
RL=32 Ohm
THD=0.1%
- 91 - mW
Normal
Output(SPK)
RL=32 Ohm
THD=1%
- 96 - mW
3.10 SIM Card Interface
3.10.1 SIM Card Application
You can use AT Command to get information in SIM card. For more information, please refer to document [1].
The SIM interface supports the functionality of the GSM Phase 1 specification and also supports the functionality
of the new GSM Phase 2+ specification for FAST 64 kbps SIM (intended for use with a SIM application
Tool-kit).
SIM900_HD_V1.05 06.23.2010
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