SimCom SIM900D EVB, Проектирование аппаратного обеспечения

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SIM900D Hardware Design
3.10.4 Referenced Electronic Characteristics
Table14: MIC Input Characteristics
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
Table15: Audio Output Characteristics
Parameter Conditions Min Typ Max Unit
load Resistance 27 32 - Ohm
Biasing voltage 1.4 V
Output swing
Voltage(single)
1.1V Vpp
Output swing
Voltage(differential)
2.2 Vpp
RL=32 Ohm
THD=0.1%
- 91 - mW
Normal
Output(SPK1P/1N
)
RL=32 Ohm
THD=1%
- 96 - mW
load Resistance 27 32 - Ohm
Biasing voltage 1.4 V
Output swing
Voltage(single)
1.1V V
Output swing
Voltage(differential)
2.2 V
RL=32 Ohm
THD=0.1%
- 91 - mW
Normal
Output(SPK2P/2N
)
RL=32 Ohm
THD=1%
- 96 - mW
SIM900D_Hardware Design_V1.04 2010.10.09
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