I have a question about the AD7400.
I connect the AD7400 with the FPGA.
The following waveform is the test input signal to the AD7400.
The signal is a sine wave of 100mV(1Hz) with the noise.
The following waveform is an output of the Sinc3 filter in the FPGA.
The noise of blue point doesn't appear in this waveform compared with the input signal.
Please let me know your advice about this cause.
The waveform showing the signal with the noise components, is that at the Vin+ pin and is Vin- ground?
Have you tried a similar input with a EVAL-AD7400EDZ evaluation board to confrim that the operation of your sinc3 filter is as expected?
How is the sinc3 filter configured regarding decimation rate?