SimCom SIM900

SIM900 Hardware Design
3.9.2 Microphone Interfaces Configuration
10pF
33pF
33pF
33pF
Close to Microphone
MIC_P
MIC_N
GND
GND
Differential
layout
Electret
Microphone
GND
GND
10pF
10pF
GND
GND
ESD
ANTI
ESD
ANTI
MODULE
Figure 25: Microphone interface configuration
3.9.3 Earphone Interface Configuration
1
2
4
3
Amphenol
9001-8905-050
SPK_P
MIC_N
MIC_P
1uF
10R
68R
33pF
GND
GNDGND
GND
Close to MODULE
Close to Socket
Differential
layout
33pF 33pF
33pF
33pF 10pF
GND
GND
GND
GND
MODULE
GND
GND
Figure 26: Earphone interface configuration
3.9.4 Referenced Electronic Characteristic
Table 10: MIC Input Characteristics
SIM900_HD_V1.05 06.23.2010
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