RC_Filter_Explorer

For a given total series resistance and total parallel capacitance, a multistage RC filter will give a much sharper rolloff than a single stage filter. The difference is very large when going from one stage to two stages and tapers off as the number of stages increase.
The main application of such a filter would be in circuits where the offset and frequency performance of an active filter would be undesirable. The series resistance can be specified and the number of stages increased to give the required attenuation while also increasing the filter bandwidth.
As the number of stages increase, the resistance and capacitance of each stage can be reduced in proportion to the total number of stages.
The total series resistance and parallel capacitance will be significantly lower than the resistance and capacitance required for a single stage with the same attenuation.
The component values are calculated using a successive approximation algorithm which converges relatively quickly.