Calculate the intrinsic elements of FET using ADS, help!

Hi everyone,

I have tried to calculate the intrinsic parameters (Cgs, Cgd, Cds, Ri, gm, gd and Tau) which are functions of the biasing conditions by ADS tool but I cannot simulate it.

How do I measure them in ADS tool?

See http://edocs.soco.agilent.com/displa...d+S-Parameters

Thank pancho_hideboo,

However I want to measure the intrinsic parameters: Cgs, Cgd, Cds, Ri, gm, gd and Tau which are as functions of source-to-gate voltage.

You can't measure these directly.

You have to determine these by fitting with varying bias points.

Some parameters such as gm and gd, you can measure directly.
See https://www.edaboard.com/viewtopic.p...759&highlight=

I want to determine the gm,gm',gm'' in ADS
how can I calculate them?

By definition...

in ADS, connect a I_Probe.i element and use diff command sequentially and find your

I mean

etc..

thanks for answer
I did it but when I sweep the Vgs and want to get gm vs. vgs but ADS gives me gm v. freq
how can I dram curve gm vs. Vgs?

Do Swept DC simulation..Put your Vgs voltage as a variable in DC Simulation block and then obtain Ids versus Vgs...
Then differentiate it..