Vdsat value for tsmc .18u

hi,

How can i find Vdsat value for for a tsmc .18u (especially for pMOS)
(for min. sized transistor L=0.18u W=0.27u)

I used Vsat value to calculate Vdsat. It worked well for nMOS. But it does not mean a lot for pMOS.

Vdsat = (Vsat*L)/un

nMOS:
Vsat=105001
L=0.18u
un=0.0276
Vdsat=0.68

pMOS:
Vsat=154523
L=0.18u
up=0.0118
Vdsat=-3???

I was expecting sth like -1V. Where is the mistake?

Re: Vds,sat value for tsmc .18u

antimage said:

pMOS:
Vsat=154523

Click to expand...

Vsat presented in units of µV ?

Doesn't Vds,sat depend on Drain Current, resp. Inversion Coefficient? See this figure:

u -> m2 * V-1 * s-1
Vdsat -> V
L -> m

So Vsat -> m * s-1

---------- Post added at 20:53 ---------- Previous post was at 20:43 ----------

And I'm actually looking for Vdsat. Not Vds,sat.[fixed]

---------- Post added at 20:55 ---------- Previous post was at 20:53 ----------

I looked for the formula from the book:

CMOS VLSI Design
Neil Weste, David Harris

antimage said:

Vsat -> m * s-1

Click to expand...

Saturation velocity, ok.

antimage said:

---------- Post added at 20:53 ---------- Previous post was at 20:43 ----------
And I'm actually looking for Vdsat. Not Vds,sat.[fixed]
---------- Post added at 20:55 ---------- Previous post was at 20:53 ----------
I looked for the formula from the book:

CMOS VLSI Design
Neil Weste, David Harris

Click to expand...

What's the definition of Vdsat in this book? I guess it's the real (or effective) saturation voltage? But it depends on Id (resp. IC) resp. Vgs. So I suppose max. Vgs , resp. max. Id (IC≈1000 , full velocity saturation) is postulated?

BTW: from your equation above, I get Vdsat = (-)2.36V , taking µ_p into account. Still a lot, doesn't make much sense.

Where did you find this equation? Couldn't find it.