SIM900D Hardware Design
Table13: 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
Table14: 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(differentia
l)
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
Normal
Output(SPK2P/2N
)
Output swing
Voltage(differentia
l)
2.2
V
SIM900D_HD_V1.02
09.04.2010
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