Hi Team,
Cusotmer design TS3A227 for the mic phone ring detection. however, sometimes it works, and somtimes it fail.
Please refer to the following good and fail case.
Case 1(good)Plug the headset first and turn on the power
1. Pin 15(DET_TRIGGER) of TS3A227E keep low
2. Pin 16(MIC_PRESENT) of TS3A227E from high to low
3. MIC can work well
Case 2(Fail)Turn on the power first then plug the headset
1. Pin 15(DET_TRIGGER) of TS3A227E from high to low
2. Pin 16(MIC_PRESENT) of TS3A227E keep high
3. MIC can cannot work
Please review schematic/layout and provide your comment why might resulted in that pin16 did not pull low while plugging headset.
Here are the schematic and layout link.
BR,
SHH