PCM2902: too much distortion and noise in the input capture

Hi, Ricardo,

Welcome to E2E, Thanks for your interest in our products.

Is it possible for you to share the schematic?, what are the noise levels you are getting?, is it possible to share a capture of the noise?.

Thanks and Best Regards,

  -Diego Meléndez López
   Audio Applications Engineer

this is the circuit I made, but the noise remains, it seems static. I already put filters and I landed and nothing. Always at the MIC input. Anyone have any ideas how to remove this noise?

recording:

Hi, Ricardo,

The schematic is quite different from the recommended diagram in the datasheet, so there are a couple points to consider:

• Vbus is missing noise-decoupling filter so any noise coupled to the USB cable will be carried to the codec. 
• This device is optimized to receive line level inputs, it does not support direct mic connection as there is no PGA to condition the signal in the front-end.
• The mic is biased to the digital power supply decoupling point, which is not recommended, digital noise could be leaking to the mic signal.
• This device does not have an integrated output amplifier capable of driving 32 Ohm loads directly, an external amplifier is required.
• Capacitor connected to pin 27 should have a value of 1µF.

The noise issue you found could be related to any of the above queries, I would recommend you to make a test removing the amplifier and applying a clean line level input, then record the signal and check if there is any change on the noise level.

Best Regards,

  -Diego Meléndez López
   Audio Applications Engineer

Thank you very much, I solved the problem by following your recommendation, and I modified the circuit, it really was that, is working now.
I have another question, do not know if I should ask here or open a new topic?
To get a dedicated driver for it is it possible? instead of installing windows automatically, does it install a dedicated driver with proper name?