This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

!URGENT - PCM2902C vs PCM2902B: Line vs microphone input terminal

Intellectual 2455 points

Replies: 3

Views: 738

I do have an urgent issue: customer is in the process of releasing a new product embedding the PCM2902C but running into some issues when using Windows 10.

As it turns out, while in the previous version embedding the PCM2902B Windows 10 detects the device as microphone with no issues in the audio settings either on the USB or on the SPDIF line, when using the PCM2902C, Windows 10 detects the device as line causing some issues on the SPDIF audio settings.

Where such an issue come from? How can customer get rid of it?

Please let me know as soon as possible

Thanks

 

3 Replies

  • Hi Jack,

    This is actually a fix from B to C revision of the PCM290x family. Originally these devices were detected as line by the windows systems previous to W7. Then something in the way that windows recognize USB devices made it to detect PCM290x and PCM290xB as mic and that was a problem as the system added too much gain. Then C revision of PCM290x family fixed this problem and these devices are detected as line in W7 and later windows systems.
    What kind of issue is it causing on SPDIF settings?

    Best regards,
    -Ivan Salazar
    Texas Instruments
  • In reply to Ivan Salazar:

    Hi Ivan,

    the issue is in the SPDIF audio level setting - since the device is detected as line the SPDIF audio level is reduced roughly by half compared to the expected level.

    Do you confirm the only way to fix it is to work on the Windows 10 driver side? Or you see HW workarounds?

    Please let me know

    Fabio

     

  • In reply to Bo345:

    Hi Fabio,

    Unfortunately I think there is no way to workaround this other than driver. Although these devices work with standard USB Audio Class.
    The S/PDIF is a line digital interface and even the volume control does not affect this interface.

    Best regards,
    -Ivan Salazar
    Texas Instruments

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.