Reduce T-Network Feedback Resistance

[JasonHathaway]

Homework Statement

Reduce the feedback resistance for the following T-Network

Homework Equations

Basic circuit analysis (Thevenin maybe?)

The Attempt at a Solution

My first though was to use Thevenin, and actually I've found some book used that method:

 

[gneill]

The Thevenin approach looks fine. Did you have some question about it?

 

[JasonHathaway]

Thank you for your quick respond. My question is whether this approach OK or not. And if the feedback resistance can be reduced more.

 

[gneill]

Thank you for your quick respond. My question is whether this approach OK or not. And if the feedback resistance can be reduced more.

The approach is good, and I doubt that the resistance can be simplified further (other than rearranging it algebraically) without plugging in actual values to reduce it to a number.

 

[donpacino]

Thank you for your quick respond. My question is whether this approach OK or not. And if the feedback resistance can be reduced more.

Typically it is a good idea to get it in the form of

G=NUM/DEN.

in other words, simplify to get rid of R2*R3/R4 in the Numerator

 

[LvW]

As an alternative, you can apply the star-triangle transformation.
After applying this transformation there will be two resistors which do not influence the closed-loop gain (and can be neglected).