We are making a multi-channel receiver board using the AD6649. The data sheet states the filter can either be 95MHz or 100MHz. If we use a lower sampling frequency of 125 MHz this would halve the filter bandwidth correct?

It would seem these bandwidths should be in relation to fs (the sampling frequency).

Hi,

You are correct, the filter bandwidths scale with the sample rate. 95 and 100MHz are for 245.76Msps, a common sample rate in the industry. If you lower the sample rate to 125Msps, then the filter bandwidths will be (125/245.76)*95 = 48.31MHz, or (125/245.76)*100 = 50.86MHz.

Regards,

David