Speaker Outputs; Figure 13: Mic1 Differential Connection; This Document Is The Sole And Exclusive Property Of Wavecom. Not To Be Distributed Or Divulged Without Prior Written; Agreement - Wavecom Integra M2106+ Product Specification

The MIC1 inputs are differential and do not include internal bias. These inputs are the standard for an
external headset or a hands-free kit.
To use these inputs with an electret microphone, bias has to be generated outside the Wireless CPU
according to the characteristics of this electret microphone.
These inputs are provided either for an external headset or a hands-free kit.
The input impedance is around 10kΩ +/- 30% between 400Hz and 4000Hz.
AC coupling is already embedded in the Wireless CPU
Signal Pin #
MIC1P 20
MIC1N 22
Differential connection
Vcc = 2.8 V from the analog power supply.
= R4 = from 100 to 330 Ω.
R1
R2 = R3 =1 kΩ to 3.3 kΩ according to the microphone characteristics.
CM = 22 pF to 100 pF.
C2 = 47 µF
R1 and R4 are used as a voltage supply filter with C2.
CM must be as close to the microphone as possible. Microphone manufacturers provide this capacitor
directly soldered on the microphone.
3.9.2

Speaker Outputs

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This document is the sole and exclusive property of Wavecom. Not to be distributed or divulged without prior written

agreement.

WA_DEV_M2106+_PTS_003-001
Pin description
I/O Reset state
I High Z
I High Z
R1
R2
C2
R3
R4

Figure 13: MIC1 differential connection

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.
I/O type
Analog Microphone 1 positive input
Analog Microphone 1 negative input
V c c
M IC1 P
CM
M IC1 N
Integra M2106+
Erreur ! Style non défini.
Description
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April, 2007
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