I need another pair of eyes.
The cutoff frequency for a 2md order multiple feedback filter is 1/(2*pi*sqrt(C1*C2*R2*R3)) which agrees with a TI application note on page 7 save for my swapped positions of R1 and R2.
However, if all values of caps and resistors are equal to 1 then the cut off frequency should be 159mHz. The calculations agree and this webtool agrees; however, Spice does not and the transfer function from the very same webtool put in MATLAB agrees with Spice.
Seriously...what the <snip> am I missing?
The cutoff frequency for a 2md order multiple feedback filter is 1/(2*pi*sqrt(C1*C2*R2*R3)) which agrees with a TI application note on page 7 save for my swapped positions of R1 and R2.
However, if all values of caps and resistors are equal to 1 then the cut off frequency should be 159mHz. The calculations agree and this webtool agrees; however, Spice does not and the transfer function from the very same webtool put in MATLAB agrees with Spice.
Seriously...what the <snip> am I missing?
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