The LTC1564 is a rail-to-rail high resolution 8th-order lowpass filter with two stopband notches, giving approximately 100dB attenuation at 2.5 times the passband cutoff frequency fC (a de-facto standard for DSP front ends). Signals with low or variable levels can be normalized with the built-in variable gain that reduces input-referred noise with increasing gain for a typical dynamic range (maximum signal level to minimum noise) of 122dB (20 equivalent bits) with 20kHz fC and 118dB at 100kHz fC on a 5V supply.