Active inductor simulation

[bicave]

Hi All,

I'm simulating active inductor and see the value imaginary of Z in SP simulation. The sim results look strange and I don't understand where is the mistake in circuit or sim.
Pls see the attached.

It seems more than one resonant value, even it negative value.
could you give me advice ? or working active inductor. This is my first design follow some paper, I expect it works to understand more about aative inductor behavior.

thanks,

 

[rezaee]

Hi bicave

I'm simulating active inductor, but I am newbie too , why you put capacitor between drain and source? are the transistors in saturation region?

 

[bicave]

inductance value is gm1.gm2/C, I add this cap for testing L.

 

[rezaee]

but I think inductance value is : Leq=Cgs2/(gm1*gm2)
and active inductor converts parasitic capacitance of transistor to inductance and no need to add external C here

 

[bicave]

Anyone know how to simulate gm, or just rely on hand calculation?

 

[dgnani]

Anyone know how to simulate gm, or just rely on hand calculation?

just use annotation of DC operating point or print function in analog design environment