I'm trying to design a 4th order Butterworth bandpass filter using Multiple feedback topology. The design requirements I am trying to achieve for this filter are; Q factor = 10, Av = 11, fc = 100kHz , BW = 10kHz.
In the book Op-amps for every one book pdf, I came across two design tables:
The First of the table correspond to my desired filter requirements with Q factor of 10 and filter coefficients values for the parameters
α. And filter calculations are given as well.
The Second table shows different 4th order coefficients values for ai,bi,Qi and uses ki.
My questions are;
1) Why the two tables for 4th order Butterworth filter have different coefficients and
Q factor values?
2) The coefficient parameters
α are the same as
3) Which is the appropriate table to use? If the second table is better for designing the filter. What are the calculations steps needed in using those coefficient parameters. Since no formulas are given in the book.