Sallen Key Filter with Resonance

I’m not sure that you need to have the components matches.

To go a little deeper into the theory, it’s important to differentiate the filter topology from the “filter approximation function”.
Examples of functions:

  • 1st/2nd order
  • Butterworth
  • Chebychev

And the topologies can be:

  • Simple RC/LC circuits
  • Sallen-Key
  • Rausch (Multi-FeedBack)

If you want a resonance, you probably want to select the 2nd order approximation function: image
Where d is the damping, the inverse of Q, the resonance.
You want Q to be higher than sqrt(2):
image

Ok, so now you need to choose the topology that suits you. If you go for Sallen-Key, you have something like that:


Where the Zx are the complexes impedances (can be either R, C, or L).
By choosing Z1,Z3 as resistors and Z2,Z4 as capacitors, you get a low-pass filter, and you can rearrange the Sallen-Key transfer function to match the 2nd order one. This way you can tell the component’s values you need, depending of the resonance and cutting frequency (maths are here: https://en.wikipedia.org/wiki/Sallen–Key_topology#Application:_low-pass_filter)

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