Common Source MOSFET Amp problem

AI Thread Summary
The discussion focuses on solving parameters for a common source MOSFET amplifier, specifically Rin, AVO, and RO, given specific values for μnCox, W/L, VA, ID, and RD. The user initially struggles with the hybrid-pi model and determining the transconductance (gm) and output resistance (ro). They realize that the biasing current ID=0.2mA is key to finding gm. After some contemplation, the user successfully figures out the necessary calculations. The conversation highlights the importance of understanding biasing in MOSFET amplifiers for accurate parameter determination.
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Homework Statement



A CS amplifier utilizes a MOSFET with μnCox = 400 μA/V2, W/L = 10, and VA=10v. It is biased at ID=0.2mA and uses RD=6k.

Find Rin,AVO,RO

Homework Equations



VAO= -gm(RD||ro)

Ro=RD||r0

The Attempt at a Solution



I drew out the equivalent circuit with hybrid-pi model. Doesn't seem to tell me much.

Not sure where to start. For the relevant equations above I'm missing gm and ro. I have a feeling "it is biased at ID=0.2mA" is a clue but I'm having trouble finding what that implies.
 
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ok nevermind I just figured it out.
 
Last edited:
Thread 'Have I solved this structural engineering equation correctly?'

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