Specifications

WM_PRJ_Q2501_PTS_002 - 001
March 2004
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3.3.6.2.6 Single ended connection example
Figure 22: MIC1 input single ended connection
VCC_AUDIO must be very “clean” to avoid bad performance in case of single-
ended implementation. That is the reason why VCC_AUDIO must be an other
2.8 V to 3 V power supply instead of VCC which is available on system
connector (pin #60).
R1 is used as a voltage supply filter with C4.
R1, R2, C4 and C5 have to be placed as close as possible to the microphone
(PCB tracks from the module connector to these components must be as
straight and parallel as possible).
C1, C2, C3 have to be placed very close to the module connector.
L1 and L2 have to be placed close to the module connector and they 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.