simulate this circuit – Schematic created using CircuitLab
I know that by using \$A_v=-G_mR_{out}\$, and \$G_m=\frac{I_{out}}{V_{in}}\$, we can get the voltage gain of this circuit.
After the small signal simplification, I got:
So, as node 1 is 0 volt, there is no current goes thru \$M_2\$, then \$I_{out}\approx g_{m1}V_{in}\$ ? So that \$G_m=g_{m1}\$ which is the \$g_m\$ of \$M_1\$? Also, the \$R_{out}\$ is \$R_{02}\$, and is the voltage gain of this circuit \$-g_{m1}R_{02}\$?
Thank you!!!!
——————————————————-UPDATE
What about this circuit?
After the small signal, I got:
Best Answer
The voltage gain is 0, because \$V_{out}\$ is connected directly to a voltage source, so its voltage will never vary, no matter what signal is present at the input.
Furthermore, M2 will probably catch fire, because its gate and drain are connected directly to the Vcc supply, which will cause a large current to flow through the FET, while it also must drop the full Vcc voltage.