Is this small-signal gain correct?

Thread starter CoolDude420
Start date Oct 2, 2018
Tags

Gain

1 reply · 1K views · last reply Oct 4, 2018

CoolDude420

Thread starter
Oct 2, 2018

Homework Statement

Handwritten small-signal gain formula Vo/Vin = -gm1(ro1||ro2||ro3) / (1 + gm3(ro1||ro2||ro3)) beside a schematic of a MOSFET circuit with M1, M2 and M3, supply VDD, bias VB, input VIN and output VOUT.

All MOSFETs (no JFETs)
Ignore body effect.

Is my gain correct? Just want to confirm.

Homework Equations

The Attempt at a Solution

Discussion

Baluncore

Science Advisor

2025 Award

Oct 4, 2018

It is a bit difficult to tell without relevant equations.
The sign is probably correct.

What are r01, r02, r03 ? Channel resistance?
What does || mean in your shorthand?
Where is gm2. Is it = GM3 ?