gm_id methodology transistors

[vinogunasekaran]

can anyone please help me why the transistors are treated as width independent figures wile we extract values from cadence for gm/id methodology.

 

[erikl]

Probably because just the W/L ratio is important?

 

[Ata_sa16]

gm = Id/2(Vov)

for a constant Id, if u increase your W/L you overdrive(ov) voltage deceases which leads to an increase in ur gm and therefore gm/Id.
You can understand it like this.

so HIGHER gm/Id belogs to large transistors (high W/L and low Vov)

But also your current can change and in order to compensate it again you have to play with W/L and ov voltage.