Hi Sirs,
My customer encounters a PCM2912A malfunction problem in system <20% low battery mode while the 5V Vbus still in regulation.
Vbus is 4.8V in this condition. The system can recognize PCM2912A UAC device on USB_CDC_D-/+. However, there is no analog output from PCM2912A.
Customer follows up PCM2912A's reference schematic. Audio architecture plays music stream by UAC interface.
With UAC path, speaker Playback Volume shows -1 in abnormal condition:
Abnormal speaker volume
Normal speaker volume
Would you please provide tips to identify this problem and the process to identify the PCM2912A in normal operating conditions?
We can send schematic by Email as needed.
Thank you and Best regards,
Wayne Chen
01/09/2019