Derive analytically the transconductance transfer function

[promach]

I am planning to derive analytically the transconductance transfer function (Iout/Vin) of this Gm2.sch circuit block.

Is my small-signal model for Gm2.sch correct ?There is one minor mistake (Vgs5 should not be zero). Could anyone spot other mistakes in the small-signal circuit ?

I am planning to start nodal analysis to formulate analytically the transconductance transfer function (Iout/Vin) tomorrow.

However, there are so many nodes in this small-signal circuit. Which nodes should I pick for a start ? I believe I need to use all nodes such that I include all mosfets and resistors into the equation ?

Besides, I am going to use http://qsapecng.sourceforge.net/index.html to verify my own hand calculation. Anyone have any experience/advice regarding this ?

 

[Valkarie]

Yes, your small-signal model for Gm2.sch looks correct with the exception of Vgs5 being zero. For nodal analysis, you should pick a node as a reference node, preferably one that has no current flowing into or out of it. You can then calculate the voltage at each of the other nodes in the circuit by applying KCL equations.As for verifying your hand calculation, QSAPECNG is a great resource to make sure your calculations are accurate. It's a good idea to check your results against any simulation software you may have access to as well.