SIM Tech SIMCom SIM800C - Microphone Interfaces Configuration; Audio Electronic Characteristic

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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
Parameter
Min
Typ
Max
Unit
Microphone biasing voltage
1.9
2.2
V
Working current
2.0
mA
Input impedance(differential)
13
20
27
KΩ
Idle channel noise
-67
dBm0
SINAD
Input level:-40dBm0
29
dB
Input level:0dBm0
69
dB