I am using AD7766 to digitize a reference AWG signal from 0.1 to 50Hz.
When I plot the output of AD7766, I see a the digitized samples has a changing phase delay relative to input frequency.
The delay appears to be from 45 degrees to 70+ degrees increasing from 0.1 to 50hz.
I am expecting a FIXED phase delay value, not a changing one since the ADC is operating at 62.5Ksamples/s and input frequency is very low.
Is this a phase response due to AD7766 internal LPF filter? The spec does not show any phase response plots.
How do I compensate for this (to flatten out the phase response)?