mos parameter for hspice simulation

[jxzhang]

hspice nrd

Newbie,
In my netlist, how to assign the AS, AD, PS, PD, NRD, NRS?
I've a netlist having the S/D_width =0.54(ECS .ini file defined)
it assign AS= W*0.54, PS= 2*W + 2*0.54, NRD(S) = 0.54/W
how to deduce the number 0.54 and AS can not equal to AD? the same
as PS and PD?

 

[Hughes]

as ad ps pd mos

The number 0.54 can be deduced from the design rule. If you want different AS and AD values, you should set them separately.

 

[jxzhang]

mos ad as pd ps nrd nrs

And what're those relations between W,L and AS, AD, PS, PD, NRS and NRD?

Thanks a lot

 

[sadfish]

mos parameter

I think you should refer to hspice manue!

 

[Hughes]

hspice as ps nrs

And what're those relations between W,L and AS, AD, PS, PD, NRS and NRD?

Thanks a lot

As shown in the figure, AS=AD=w*a, PS=PD=W*2+a*2

 

[bastos4321]

AS=AD=w*a, but PS=PD=W+a*2 because the lateral side of the channel do not count. However, some people use 50% of the lateral side of the channel as a worst case.

PS=PD=W*1.5+a*2.

In "digital integrated circuit design" by Ken Martin they use

lamp = (minimum L) /2

AD=W*5*lamp = AS
PD=PS=W+10*lamp

Ex: for 0.18um lamp=0.18um/2

Bastos

 

[thcm]

Cd=Carea+Csw+Cswg
=AD*Cjd+(PD-Weff)*Cjbdsw+Weff*Cjbdswg


[/img]

 

[jxzhang]

It confused me! By process which one or what rule is exactly correct?

 

[staric]

But I don't know whether it is necessary that these parameter are used in the simulation. I think W and L is enough.

 

[Hughes]

But I don't know whether it is necessary that these parameter are used in the simulation. I think W and L is enough.

W and L are required, but not the only parameters. Providing AS, AD, PS, PD will give more accurate results.

 

[bastos4321]

You can use Hspice switch to calculate AD, AS, PD and PS, but I usually include these parameteris in the netlist. The effect of diffusion capacitance has a great impact on circuit behavior. You can not use only W and L in a design, its a big mistake.

Bastos

 

[jxzhang]

what is "HSPICE switch" ?