Consider the component R of the Frequency Selective Network in a 4th order S&K LPF with Input Buffer Stage (Butterworth Filter Response)
I have noticed that as the value of R increases, the attenuation at the stop band of the Butterworth response improves (decreases). What is the explanation for this?
The rest of the parameters such as passband gain and frequency cut off can be explained through the common formulas but for the stop band attenuation, how is this rationalized?
Thanks=)