Equivalent Small-Signal Resistance of a MOSFET Circuit

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SUMMARY

The discussion focuses on deriving the expression for the equivalent small-signal conductance (Geq) of a MOSFET circuit. The key equation presented is Geq = i_t / v_t, where vt is defined as vg, vs is set to 0, and vd is -vt. The participant expresses uncertainty in their approach using Kirchhoff's Current Law (KCL) at node vg and seeks validation of their small-signal model. The consensus emphasizes the importance of correctly applying KCL to derive Geq accurately.

PREREQUISITES
  • Understanding of small-signal analysis in MOSFET circuits
  • Familiarity with Kirchhoff's Current Law (KCL)
  • Knowledge of equivalent conductance and resistance concepts
  • Basic circuit analysis skills
NEXT STEPS
  • Review small-signal models for MOSFETs
  • Study the application of Kirchhoff's Current Law (KCL) in circuit analysis
  • Learn about equivalent resistance calculations in electronic circuits
  • Explore practical examples of small-signal conductance derivations
USEFUL FOR

Electrical engineering students, circuit designers, and anyone involved in analyzing MOSFET circuits and small-signal parameters.

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Homework Statement



Derive an expression for the equivalent small-signal conductance Geq (or resistance Req).

Homework Equations



Geq = \frac{i_t}{v_t}

vt = vg

vs = 0

vd = -vt

The Attempt at a Solution



Attachment - EE HW 2

I drew the small-signal circuit, from what I gather it seems to be correct although I am a bit rusty on that. I began by using KCL at node vg and solving for Geq but I'm really unsure as to whether I've started this right. Looking at my work so far, to me, it seems to be on track for solving for Geq. If someone could just simply check my work/small-signal model over from what I have so far it would be greatly appreciated to earn some confidence on continuing my work! Thank you.
 

Attachments

  • EE HW 2.png
    EE HW 2.png
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Anyone have any insight on finding this equivalent resistance? I've been trying to use KCL but my answer continues to look even worse. Any help or insight would be greatly appreciated!
 

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