Specifications

WM_PRJ_Q2400_PTS_001 - 003
6th November 2002
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2.11.3.2.2 Single-ended connection
Typical implementation:
L1
C1
C2
MIC1P
MIC1N
V
AUDIO
C4
R1
R2
L2
C3
C5
Figure 7 : MIC1 inputs (single-ended connection)
Note:
V
AUDIO
must be very “clean” in single-ended connection (for example,
VCC plus filter cell like RC or LC).
R1 = from 100 to 330
Ω
R2 = usually between 1K
Ω
and 3.3K
Ω
as per the V
AUDIO
voltage level and the
microphone characteristics
C1 = 10pF to 33pF
C2 = C3 = C5 = 47pF to 100pF
C4 = 47µF
L1 = L2 = 100nH
R1 is used as a voltage supply filter with C4.
C5 has to be the nearest possible to the microphone. Microphone
manufacturers provide this capacitor directly soldered on the microphone.
C1, C2, C3 have to be very close to the WISMO Quik Q2403 Series connector.
L1, and L2 has to be put near the WISMO Quik Q2403 Series connector and
can be removed according to their environment (ground plane, shielding ...etc).
The best way is to plan all the components and to remove those which are not
necessary to filter out the TDMA noise on the audio path.
Pin description
Signal Pin # I/O I/O type Description
MIC1P 42 I Analog Microphone 1 positive
input
MIC1N 44 I Analog Microphone 1 negative
input