PCM2906: PCM2906 Windows 7

Yuriy Lapushev

Part Number: PCM2906

Hi!

I have some problem with my ADC in Windows 7.

I have built PCM2906 based audio ADC and it's works fine but in first three-five minutes. After this device is switching off and new USB device connection is possible only after windows restart.

What can be wrong? Power supply? Or maybe external crystall oscillator capacitors? Maybe something more...

Thanks for your answer!

over 7 years ago

0 Diego Melendez over 7 years ago

TI__Guru 57800 points

Hi, Yuriy,

The PCM1906C is fully compatible with Windows 7, as you can find in one of the available App Notes for this device (Key Differences Between the PCM290x and PCM290xC). This indicates that the issue is not related to the firmware of the device. One thing to note is that you need to make sure that you are using the "C" Version of the PCM, could you please verify this?.

Best Regards,

-Diego Meléndez López
Audio Applications Engineer

0 Yuriy Lapushev over 7 years ago in reply to Diego Melendez

Prodigy 140 points

Hi!

Thanks for you response!

I just checked and I really have "C" version PCM2906.

What can I do more?

Thanks!

0 Diego Melendez over 7 years ago in reply to Yuriy Lapushev

TI__Guru 57800 points

Hi, Yuriy,

Thanks for the feedback. If possible could you please share the schematic of the PCM2906C of your board?, this way we can determine if there are any visible problems. The load capacitors should not represent a big issue as in general the crystals are not a common source of issues. Could you check that all the power supplies of the PCM2906C are valid at the time of the failure?. It is also possible that the host controller is having issues with the detected driver from the PCM.

Best Regards,

-Diego Meléndez López
Audio Applications Engineer

0 Yuriy Lapushev over 7 years ago in reply to Diego Melendez

Prodigy 140 points

Hi, Diego!

Thanks very much for your help!

Just cheked yesterday all modes while working and after switching off. So, all voltages is OK, but Vcom (14 pin) decreasing to 0.76V after switching off. Maybe it can help.

Here is my board schematic.