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Butterworth Low/High Pass L/C Filter Calculator

The Butterworth filter is maximally flat. It is optimal in the sense that, of all possible filters with a monotonic passband (not changing in the passband) and a monotonic stop band (not changing in the stop band), it has the minimum attenuation in the pass band.

This type of filter is necessary for conditioning analog signals where you don't want to distort the signal too much. E.g., you might want to hook up an sensor to an ADC to get some readings. But the problem is that, you have some high frequency noise. So you would want to eliminate this noise without affecting the sensor readings too much. In this case, go with a Butterworth filter. Butterworth filters are also used for Anti-aliasing applications.

Just enter the required data and click anywhere outside the data area.

Chebyshev Low/High Pass L/C Filter Calculator

The Chebychev filter is optimum in the sense that, of all filters with a monotonic stop band (ripple allowed in the passband), it has the steepest transition region.

This type of filter might be used when the frequency content of a signal is more important than having a constant amplitude. E.g., you might have a digital signal. The amplitude has only two states, 0 and 1, so accurate rendering of the amplitude is not important, when it is passed through a filter. In this case, the output signal start resembling a sine wave. But that's ok, as long as the distance between 0/1 and 1/0 transitions are preserved.

Just enter the required data and click anywhere outside the data area.