Vary W and L parameters in DC analysis

[Garfild666]

Hi, I'm beginner in hspice and I need to plot I-V(drain) graphic of an NMOS using 2 different W and L to see the difference between V(sat) of a alrge NMOS and a smaller NMOS.
I want to do this using .data statement
but a try many ways and nothing works...
if someone can help...please...
I appreciate the attention!
Thnks a lot!

*
.include processo.inc
.param vdd=3.2
.param wgp=300u 
.param lgp=180u

Vd D1 0 dc 3.2
Vg G1 0 dc 3.2
Vs S1 0 dc 0

m1 D1 G1 S1 0 ntran(wgp lgp) 

.dc vd 0 3.2 0.01 sweep data=tr
.option post

.data tr 
wgp lgp
300u 180u
300m 180m
.enddata

.end
*processo.inc is the card of nmos tecnology that I'm using

 

[keith1200rs]

I would have expected the transistor to be defined as

M1 D1 G1 S1 0 ntran w=wgp l=lgp

Are you using Hspice?

Keith.

 

[Garfild666]

Yes I'm using Hspice.
by default w is the first parameter and l is the second...
than I don't need to put w=wgp and l=lgp...
I already try to put this but nothing changes...
Thnks for reply!!!!

 

[keith1200rs]

If you change the .param statements at the top do the results change? Does the list file produce any errors? (it might be helpful to attach the list file).

Keith.

 

[jardila]

Hi,
Ok, the line with the .include stament is wrong. The correct stament is:

.include 'processo.inc' $$ Note the quotes.

if this does not solve the problem, verify the correct path for the process.inc file. You must put complet path in the .include statement.

Best Regards,

 

[sjamil02]

I would normally use .ALTER statement for this purpose. Eg.

sj