I got EVAL-AD7176-2SDZ (Rev-A), and I use it to test audio signal.
I use AD7176-2 to sample a pure 12.5 kHz 0.1 Vrms sine wave, and sample rate is 125kHz.
But there is a stable low frequency noise as below picture, so it make the wave envelope is unstable.
My setting as below:
The attachment is my test data.
Do you have any idea about this problem?