Hello all, The value of W in the transistor refers to total width or width per finger? i.e. if I need 3/0.5 transistor to have nf=2 , m=2 it will be W=0.75 L=0.5 nf=2 m=2 or W=1.5 L=0.5 nf=2 m=2 ?

It can be either. But if you want to follow the official BSIM standard, then W is the total width. But to make that work correctly in ngspice, you need a .spiceinit file with the contents

set ngbehavior=hsa

. This file is found in the

open_pdks

installation as

sky130A/libs.tech/ngspice/spinit

and just needs to be copied to the directory where ngspice is being run, and renamed to

.spiceinit

.

ok thanks