If you specify a corner frequency and a capacitor value it will calculate the rest of the circuit elements and will plot the circuit diagram as well as the magnitude and phase responses.

User can choose among Chebyshev 0.5 dB ripple, Chebyshev 2 dB ripple, Butterworth and Bessel filters.

It also has "Custom Filter" option which allows the user to enter a specific frequency correction factor (fn) and the gain (K) factor.

This is a very useful feature as it allows one to design higher order filters as well where each stage is a 2nd order filter.

For a given multistage filter, the corner frequency is the same for each stage however the fn and K values are different for each stage.

Reference:Art of Electronics by Horowitz&Hill
All the resistance values are in Ohms, capacitor values are in nanofarads and the frequency is in Hz.

This user program was send to us by: Meric Ozcan
This is just one of the MORE THAN 75 FREE user programs for CplxCalPro the most powerful calculator available for the palm platform.