PCM6360-Q1: Gain question

Peter Xu

Part Number: PCM6360-Q1

Tool/software:

Hi team,

When my customer was testing the microphone input, they observed that as the microphone input decibel level increased, the output suddenly dropped from the maximum value to the minimum value. They would like to know whether the PCM6360-Q1 could exhibit such a sudden drop from maximum to minimum when the input reaches its upper limit.

Regards,

Peter

2 months ago

0 Daveon Douglas 2 months ago

TI__Mastermind 27320 points

Hi Peter,

Is diagnostics enabled in this system? If so, are you able to reproduce this issue, check for any short conditions on this channel?

Regards,

0 Peter Xu 2 months ago in reply to Daveon Douglas

TI__Expert 6120 points

Hi Daveon,

They got this result in normal mode.

You can check their register dump.

Regards,

Peter

0 Daveon Douglas 2 months ago in reply to Peter Xu

TI__Mastermind 27320 points

Hi Peter.

This is most likely the audio clipping as a result of the input signal exceeding the full scale limits.

Since the device is configured for differential, AC-coupled microphone input, the max input signal allowed is 2Vrms. Does the input signal exceed this and what are the pull-up resistor values used following the AC cap up to MICBIAS?