- #1
Waxterzz
- 82
- 0
Homework Statement
Calculate the impedance Zin[/B]
Homework Equations
The Attempt at a Solution
[/B]
I cut VDD and the DC current source at the top.
Put in test DC voltage
VTest - 10* ITest = VGS (because voltage "after" the resistor = the voltage at the gate and the drain, and source is to ground.
times gm to find current trough NMOS:
gm [VTest - 10* ITest ]= gm VGS
This equals VTest / 10 (current through resistor would be the same as current through NMOS
rearranging
VTest / I Test = 10*gm / (gm - 1/10) = Zin
Zin = 101.01 k Ohm ?This is probably wrong.