Hey,

I was listening to a talk where the speaker was talking about the concept of sensitivity functions ( seen in control systems) used to determine how variations in parameters can affect the overall transfer function in integrated circuits. The first two slides explain the definition and concept.

I was hoping some here with a circuit design or control systems background could explain how they derived the expression for the sensitivity function for the example where they try to boost an amplifiers gain using negative resistance.

How do they get the sensitivity of Ave wrt to x be - x/(1-x) ? The speaker mentioned their are tables which show that functions of the nature 1/(1-x) reduce to -x/(1-x).

Can someone point me in the right direction?

https://imgur.com/a/mjOhG

Maks wrote on Mar 1^st, 2018, 4:22pm:


Hey, thanks for taking the time to answer.

Yeah I did the math the same way where (x/y) * (dy/dx) and I got the same result like you, with a positive sign.
I will try to contact the author of the slides.