Hello all,
I am facing the following issue: When I attach/detach a (a properly coupled*) active microphone multiple times, the ADC produces a strong noise and it does not return to normal operationeven after re-sending the whole set of programming sequence to TLV320AIC3204 SPI port, unless we issue a software reset prior to the programming commands. Unfortunately, this reset is audible by the end user.
It seems that an ADC overflow (register P0_R42, bit 3) is detected along with the ADC malfunctioning event. However, most of the times, this overflow leads to a short-duration (a few msec) noise then the ADC returns to normal operation without any intervention. Is it possible that a simple ADC overflow is responsible for these problems? (I would expect just distortion until amplitude return to normal levels)
Best regards
*Microphone coupling is accomplished via 1uF ceramic capacitors and 1000Ohms resistors in series with IN2_L, IN_R inputs. Schottky diodes to AVDD and ground protect from ESD and surges. MIC/ADC settings:
fs = 8ksps, sample size = 16bit
Power Tune Mode = PTM_R4
Decimation Filter A
Processing Block = PRB_R1
AGC = off
Digital Gain = 0 dB
Differential input from IN2L, IN2R pins
Input resistance = 20K for both pins
Analog LDO = on, 1.77V
Digital LDO = on, 1.77V
Device CM voltage = 0.9V
