Sierra Wireless WISMO218 Benutzerhandbuch
WA_DEV_W218_PTS_002
Rev 005
Page 53 of 109
Product Technical Specification &
Customer Design Guidelines
Figure 16. Example of MIC Input Differential Connection without LC Filter
The capacitor C1 is highly recommended to eliminate TDMA noise. Note that C1 must be close to the
microphone.
microphone.
Recommended Components
Component
Description/Details
Notes
C1
12pF to 33pF
needs to be tuned depending on the design
C2, C3, C4
47pF
needs to be tuned depending on the design
L1, L2
100nH
needs to be tuned depending on the design
Microphone Single-Ended Connection Example
When single-ended connection is used for MIC, MICN is just left open.