WM_PRJ_Q2501_PTS_002
- 001
March
2004
confidential ©
Page:
37 / 79
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3.3.6 Audio interface
3.3.6.1 General
Two different microphone inputs and two different speaker outputs are
supported.
The WISMO Quik Q2501 also includes echo cancellation and noise reduction
features improving quality of hands-free function.
In some cases, ESD protection must be added on the audio interface lines.
3.3.6.2 Microphone
inputs
3.3.6.2.1 General
description
The difference between main microphone inputs (MIC2) and auxiliary
microphone inputs (MIC1) is the availability of an internal biasing for an electret
microphone.
For both microphone paths the connection can be either differential or single-
ended but using a differential connection in order to reject common mode noise
and TDMA noise is strongly recommended.
When using a single-ended connection, be sure to have a very good ground
plane, a very good filtering as well as shielding in order to avoid any
disturbance on the audio path.
3.3.6.2.2
Main Microphone Inputs (MIC2)
MIC2 inputs include an internal convenient biasing for an electret microphone.
This electret microphone can be directly connected on these inputs, either in
differential or single-ended mode.
AC coupling is already embedded in the module.
Pin description
Signal
Pin #
I/O
I/O type
Description
MIC2P
66
I
Analog
Microphone 2 positive input
MIC2N
68
I
Analog
Microphone 2 negative input
Summary of Contents for WISMO Quik Q2501
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