Small Signal Analysis of Common Gate (CG) MOSFET Amplifier

This CalcTown calculator calculates the small signal voltage gain of a Common Gate (CG) MOSFET amplifier, working in the saturation mode.

* Please note that body effect has been taken into consideration only for calculating the small signal output resistance and not for the current calculation in DC analysis.

Small Signal Analysis of Common Gate (CG) MOSFET Amplifier

R_si

K-Ohm

R_D

K-Ohm

R_L

K-Ohm

MOSFET constant (K_n)

uA/V²

DC Bias Drain current (I_D)

Calculate Drain Bias current here

Result

Small signal transconductance

uA/V

Small signal Voltage gain

V/V

Small Signal Current Gain

A/A

Click here to view image

where

K_n=1/2(k`W/L)=MOSFET constant

g_m=Small signal transconductance

λ=V_A^-1 =Inverse of Early Voltage

and the corresponding small signal equivalent circuit is