Butterworth Filters

The Butterworth Filter is the filter type that results in the flattest pass band and contains a moderate group delay.

A standard Butterworth Filter's pass band attenuation is -3.01dB. However, Filter Solutions allows the user the option of selecting any pass band attenuation in dB's that will define the filters cut off frequency.

Filter Solutions also offers the user the option of placing user-defined zeros in the stop band. Such a filter with stop band zeros is no long a true Butterworth Filter, but is still in the Maximally Flat filter family.

Below are examples of Butterworth low pass, high pass, band pass and band stop filters and the low pass step response.