Is Id(drain) current equal to Is(source) when voltage source connected (CG Amp)?

[raj_007]

Is Id(drain) current equal to Is(sourc) when volage source connectd (CG Amp) ...??l

Hi,

I am finding Current gain of Common gate amp with gate biased and applying supply at source.
If I measure Iout/Iin getting 1 as current gain till mosfet is ON and when mos enters to cut off it is giving gain of sudden spike around 20.

and also by varying input sweep in steps 0.01/0.001/0.0001.

In this case source current is different than drain current.

Please can anyone give solution for this problem.

Note: CG amp should be unity gain.

Thanks,
Raj

 

[nitishn5]

Re: Is Id(drain) current equal to Is(sourc) when volage source connectd (CG Amp) ..

Can you give the circuit that you are using for your experiment?
At what voltage is the Gate and the Drain set at?

It seems that when you enter the Cut-Off region, the Drain to Body diode turns On and you see a current gain.
I'm just guessing.