Interview questions about Hspice & Spectre

[sudip]

dear friends,
do you have any idea of interview questions asked on hspice and spectre, for experienced people as a analog front-end designer. Thanx in advance.

 

[paladinzlp]

hspice & spectre

hspice:sim slow,not convergence sometimes,high resolution.
spectre:sim fast, easy to converge

 

[sudip]

Re: hspice & spectre

hi friend,
what do you mean by "converge"? please make it clear to me...

 

[pmr9]

Re: hspice & spectre

Hi ,while running, simulator's algorithms are able to track fine values of V&I set in ur simulator ,its a iteration process ..genlly for the first cut simulator uses basic newtons Raphson method ..if convergence is not achieved it go for next advance algorithms.
So m any techniques r there to get converge ur sim like setting no. of iterations too high or increasing step size and using some conv options in the analysi statement itself etc.

 

[waxtomato]

hspice & spectre

BTW, be sure to answer "don't know' if you don't. Expert will know what you know when you open your mouth.

 

[UniqueICs]

Re: hspice & spectre

Paladinzlp, as far as i understood You think that Spectre simulates faster and better all type of circuits than HSPICE does?

 

[zhangsai04]

hspice & spectre

I think hspice is more accurate.

 

[somo]

hspice & spectre

yes hspice is better

 

[psmon]

hspice & spectre

Hspice is better in which kind of simulations? Transient is ok but definitely not noise.

 

[FastSpice]

Re: hspice & spectre

Spectre is better in analog and RF simulation. Hspice is more used in digital and signal integrity simulation.

-FastSpice

 

[dozy_walia]

hspice & spectre

How can i run HSPICE ??
I have modelled it using spectre!

 

[FastSpice]

Re: hspice & spectre

As far as I know, Hspice can't run Spectre models.

Not sure about the reason to run Hspice on Spectre models. In the old days, another strength of Hspice was its proprietary models. If you have Spectre models, there is no reason to use Hspice.

FastSpice

 

[psmon]

hspice & spectre

Hspice and Spectre have slight different syntax. Need to change the starting few characters in each line.

 

[dozy_walia]

hspice & spectre

psmon!!

Which chracters and how?

 

[sudip]

Re: hspice & spectre

if you have designed something using hspice then to run it using spectre use following "simulator lang=hspice"