I've been using the AD8236 to make an EMG amplifier. I connected a second order low pass MFB butterworth filter at @20Hz cutoff , which filters the AD8236 output and feeds it to the reference pin. I am not pleased with the results. while the DC correction seems to work well, at lower frequencies the signal is not attenuated much, and instead is kind of a square wave output even at low amplitude input.
I was wondering, does the ref pin operate with a varying signal? say, if i input a DC shifted sine wave at the Vref, will the output contain the same signal added to it?