Why variation of Gm in effective voltage is not considered in transconductance?

[Shans60]

Hi we all know that transconductance depends on the effective voltage but its said that variation in gm with that effective voltage is not considered... is it correct if so what is the reason...

 

[venkat3271]

Re: transconductance

First u want to be clear with the expression of Gm..

Gm=constant *sqrt(W/L) * sqrt (Id)....


Gm depends on root of W/L and drain current...

 

[A.Anand Srinivasan]

Re: transconductance

Mr.venkat3271 for ur kind information the drain current Id of a MOSFET depends on the effective voltage.... please do refer some material on MOSFET.....

 

[venkat3271]

Re: transconductance

yes.. Of cource Gm is dirctly proporationl to Vgs- Vt , which can be expressed in Id term, Thats what i have written that in

Gm=constant *sqrt(W/L) * sqrt (Id).... this expression..

Any thing wrong with this expression??..

ur suggestions r welcome...