SIM900D Hardware Design
3.10.2 Microphone Interfaces Configuration
10pF
33pF
33pF
33pF
Close to Microphone
GND
GND
Differential layout
Electret
Microphone
GND
GND
10pF
10pF
GND
GND
ESD
ANTI
ESD
ANTI
MODULE
MIC1N
MIC1P
Figure22: Microphone interface configuration
3.10.3 Earphone Interface Configuration
1
2
4
3
Amphenol
SPK2P
MIC2N
MIC2P
1uF
10R
100R
33pF
GND
GND
GND
GND
Close to MODULE
Close to Socket
Differential
layout
33pF
33pF
33pF
33pF
10pF
GND
GND
GND
GND
MODULE
GND
GND
Figure23:
Earphone interface configuration
3.10.4 Referenced Electronic Characteristic
SIM900D_HD_V1.02
09.04.2010
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