Differential Audio Connection - Sierra Wireless WISMO228 Product Technical Specification & Customer Design Manuallines

For differential connections, it is necessary to add a 2.2KΩ resistor from MICN to GND to have a
proper bias of the microphone.
Differential Audio line is
always in parallel
For single‐ended connections, the negative pole of the microphone, MICN, should be connected to
GND.
WA_DEV_W228_PTS_002
Figure 26. Audio Track Design
Figure 27. Differential Audio Connection
Rev 001
Product Technical Specification &
Customer Design Guidelines
Page 64 of 108