What with transistormodel inaccuracy in avanced technology?

Matchasm said:

Currently, I am designing a real-life product in a state-of-the-art CMOS process for a large company.

I don't actually look into the book nowadays, because I know output resistances and one basic saturation formula by heart:

Id = 1/2 * mu * cox * W/L * (Vgs-Vth)^2

Click to expand...

This is something which I find rather peculiar. As a student, I'm working on my masterthesis in a 0.35 um technology. It is far from evident to apply the formula stated above, for Vds > Vdsat.

Granted, from the knowledge of the output resistance, it should be possible to calculate lambda and use the formula
Id = 1/2 * mu * cox * W/L * (Vgs-Vth)^2 (1 + lambda*(Vds - Vdsat))

Now, how do you experts cope with the less accuracy of LEVEL 1 mosfet models in a more advanced technology?

Another issue I have is about the approximation of parasitic capacitances such as gate-source capacitance, gate-drain capacitance?

BTW matchasm, how do you learn output resistances by heart?

Any thoughts concerning these issues would be highly appreciated and very helpful!

Thanks!

Re: What with transistormodel inaccuracy in avanced technolo

Ok, I think I made a beginners mistake by not using the search option...

I found interesting reflections on my problems in the next topics:



Although I could use some further oppionions in this matter. I never thought that analog circuit design would be that much trial and error. But I suppose that getting along with the technology is just a first step in the life of an analog IC designer.

Thanks!