# How would you go about getting the small signal transfer function for this inverter circuit?

Joined Mar 25, 2019
5
Hey everyone, I was talking with a graduate student the other day about small signal transfer functions and how to create them. He drew this circuit for me and asked if I could come up with a small signal transfer function for it. The circuit he drew was this:

I could not come up with a transfer function so I started looking around online to see if I could find similar examples but there seems to be nothing out there that shows how to find this transfer function. Does anyone know how they would go about getting the small signal transfer function or have any links that would show how so I can quench my curiosity about this?

Joined Mar 10, 2018
4,057
Assign the inverter symbol as a amp with -G gain, then just
use standard Laplace to crank out the T(s). Note consider the
G element as ideal, Zin = infinite, Zout = 0.

Regards, Dana.

#### MrAl

Joined Jun 17, 2014
9,633
Hey everyone, I was talking with a graduate student the other day about small signal transfer functions and how to create them. He drew this circuit for me and asked if I could come up with a small signal transfer function for it. The circuit he drew was this:
View attachment 176476
I could not come up with a transfer function so I started looking around online to see if I could find similar examples but there seems to be nothing out there that shows how to find this transfer function. Does anyone know how they would go about getting the small signal transfer function or have any links that would show how so I can quench my curiosity about this?
Hello,

You really have to know the details of the inverter. Things like gain, output impedance are important.
Without knowing the output impedance you cant solve this ever, except symbolically.

If you assume the output impedance is resistive only, then you can use a voltage divider formula to get the symbolic output knowing the gain.but there could end up being three different solutions depending on choice of output R and L and C.