Gm/IDS vs Vov plot in Cadence?

[dtzounakos]

My question is how to plot gm/ids vs Vov in Cadence. I know how to plot gm/ids vs

vgs but i don't know how to define custom equation in calculator such as Vov=Vgs -Vth!

Does anyone know how to do this?

Thanks a lot!

 

[JoannesPaulus]

to plot a waveform versus any equation you should plot both in the same waveform window then go to the axes menu and in the "Plot vs." scroll down menu, choose your equation.
I hope it helps!

 

[dtzounakos]

Thanks a lot. But what i ask is how to define Vov=Vgs-Vth in ordr to plot gm/Ids vs Vov! If you how to to define Ids/(W/L) in order to plot Gm/IDS vs Ids/(W/L) I will appreciate it!!

Thanks!

Added after 3 minutes:

Thanks a lot! But what i ask is how to define Vov=Vgs-Vth (in waveform calculator i suppose) in order to plot Gm/Ids vs Vov! Also, if you know how to define IDS/(W/L) in order to plot Gm/Ids vs Ids/(W/L), I will appreciate it!!

Thanks!

Added after 3 minutes:

Thanks a lot! But what i ask is how can i define Vov=Vgs-vth (in waveform i suppose) in order to plot Gm/ids vs Vov!Also, i will aprreciate it if you know how to define IDS/(W/L) in order to plot Gm/IDS vs IDS/(W/L).

Thanks!

 

[JoannesPaulus]

In the calculator click on OP and then select the transistor you want to know the VTH. A pop-up window will appear. In the scroll down menu of the new window look for VTH. You can then use that in your equations.