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SIM800C_Hardware_Design_V1.00 32 2014-10-30
SPKP
Close to speaker
ESD
ESD
10pF
33pF
33pF
33pF
Module
SPKN
10pF
10pF
10pF
33pF
33pF
33pF
10pF
10pF
Figure 29: Speaker reference circuit
4.7.2. Microphone Interfaces Configuration
Electret
Microphone
The lines in bold type should
be accorded to differential
signal layout rules
These components should
be placed to microphone
as close as possible
MICP
Module
MICN
ESD
ESD
10pF
33pF
33pF
33pF
10pF
10pF
Figure 30: Microphone reference circuit
4.7.3. Audio Electronic Characteristic
Table 14: Microphone input characteristics
Microphone biasing voltage
Input impedance(differential)