Specifications

Product Technical Specification & Customer Design Guidelines
Interfaces
© Confidential
Page: 56 / 116
This document is the sole and exclusive property of WAVECOM. Not to be distributed or divulged without
prior written agreement.
WA_DEV_Q64_PTS_001-003 January 9, 2009
3.11.4 Application
3.11.4.1 Microphone
3.11.4.1.1 MIC1 Differential Connection Example
Figure 13: Example of MIC1 input differential connection with LC filter
*:Z1 is from 200Hz to 4kHz. For more characteristics refer to chapter 3.11.1.1.1.
Note: Audio quality can be very good without L1, L2, C2, C3, and C4 depending on
the design. But if there is EMI perturbation, this filter can reduce the TDMA
noise. This filter (L1, L2, C2, C3, C4) is not mandatory. If not used, the
capacitor must be removed and coil replaced by 0 Ω resistors as shown in the
following schematic.