Abstract: A device and method is provided for filtering frequency components of an electrical signal above a selectable low pass cutoff frequency which is changeable within a designated range. An input filter having a fixed low pass cutoff frequency provides aliasing protection for a first of at least three clock driven filter stages respectively having variable low pass cutoff frequencies proportional to a clock rate of a received clock signal. The overall selectable low pass filter is determined at an intermediate stage of the clock driven filter stages. Clock rates of respective clock signals applied to clock driven stages proceeding the intermediate stage having the selectable cutoff frequency are adjusted so that each provides aliasing protection for the next. Similarly, the low pass cutoff frequencies of clock driven filter stage succeeding the intermediate stage having the selectable cutoff frequency are adjusted to eliminate staircasing distortion in the output signal.