
xE922-3GR Hardware User Guide
1VV0301272
Rev.0.8 2017-01-05
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Page 85 of 112
The following figure shows typical single ended connection concept for electret microphones (AC coupling
value for low cut off frequency @ 300Hz):
The MICP/MICN should be routed close together in order to minimize interference noise.
Differential mode can be interesting when feeding the MIC input from a differential pre-amplifier.
Parameters analog microphone:
Parameter
Min
Typ
Max
Unit
condition
BW
20
Hz
Lower limit
4
20
kHz
Upper limit
DR
72
dB FS
CCIR
Gain 0dB, BW 300-8000Hz, input 0.8Vpp diff
THD+N
-55
dB
Ref signal -10 dB FS
Freq response
-1.2
0.5
dB
Ref signal -20 dB FS
Input
differential
1.6
Vpp
Gain 0dB, 0 dB FS
R_in
25
kOhm
Differential
C_in
5
10
pF
PSSR
45
66
dB
Gain 0 dB