Appendix.
MIC Flow Chart & Solution
13-A) Check Audio Signal Level U900 Pin 5,6 U901 Pin 5,6 After putting audio signal in MIC
Check Soldering
Yes
No
A few hundreds of mV Signal
Replace U900, U901
are measured ?
13-1) Test!!
MIC Working !
Reference MIC Signal
GSM Handsets Lab.
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