[sdiy] How to add stability cap to voltage follower?

[Scott Juskiw]

I was wondering if someone can help me with a minor design issue.

I'm familiar with the technique of adding a cap in parallel with the 
feedback resistor in an inverting amplifier to add stability. But how 
do you add the same kind of stabilizing cap to a non-inverting 
amplifier?

The circuit in question is a state variable filter and I want all the 
outputs to be non-inverting. I started out with a simple inverting 
amplifier, gain of -1, with Rin=100K, Rfeedback = 100K, and 1K 
hanging off the output. To this I added a 22 pF cap in parallel with 
Rfeedback. But now I realize that I need a non-inverting amp. OK, a 
voltage follower is simple enough to build. But I'm not sure how to 
hook up a stabilizing cap to that. I can put Rfeedback back in and 
add the cap in parallel with that as I had with the inverting 
amplifier. It doesn't seem to hurt anything, but is it doing good? Or 
should I not worry about adding the cap?