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Simulators >> Circuit Simulators >> Cadence Corner Analysis Tool
https://designers-guide.org/forum/YaBB.pl?num=1171016468

Message started by Visjnoe on Feb 9^th, 2007, 2:21am

Title: Cadence Corner Analysis Tool
Post by Visjnoe on Feb 9^th, 2007, 2:21am

Dear all,

I experience problems when I set up a corner analysis using ADE and then export it to an OCEAN script
(or even without exporting it).

Basically, in the OCEAN script there's a statement like this:

Code:

corSetMeasExpression( "ton" "(cross(VT(\"/up\") 0.9 -1 'falling) - cross(VT(\"/up\") 0.9 -1 'rising))" )

Of course, for corner analysis, I would like to replace the fixed 0.9 by Vdd/2.
Vdd is certainly a parameter of my netlist and added to my corner setup file .pcf.

When I replace the above code by the following:

Code:

corSetMeasExpression( "ton" "(cross(VT(\"/up\") "Vdd/2" -1 'falling) - cross(VT(\"/up\") "Vdd/2" -1 'rising))" )

my OCEAN corner script is not able to output these results over corners. Furthermore, the corner analysis GUI
reacts in the same way (only a fixed number works...)

Has anyone a solution for this? I can't imagine this cannot be setup under Cadence...

Kind Regards

Peter

Title: Re: Cadence Corner Analysis Tool
Post by ACWWong on Feb 9^th, 2007, 2:30am

try VAR("Vdd")/2 instead of 0.9

Title: Re: Cadence Corner Analysis Tool
Post by Visjnoe on Feb 9^th, 2007, 5:24am

Dear ACWong,

thanks for your reply.

Is there anywhere in the documentation this is mentioned? I went through all relevant manuals/user guides and could not find anything...

Kind Regards

Peter

Title: Re: Cadence Corner Analysis Tool
Post by Visjnoe on Feb 9^th, 2007, 5:38am

Dear,

the VAR("Vdd")/2 suggestion does not seem to work...

???

Kind Regards

Peter

Title: Re: Cadence Corner Analysis Tool
Post by Visjnoe on Feb 9^th, 2007, 5:46am

Dear ACWong,

my mistake, it DOES work, it is just case sensitive.

Any pointer to the relevant piece of documentation would be welcome!

Kind Regards

Peter

Title: Re: Cadence Corner Analysis Tool
Post by ACWWong on Feb 9^th, 2007, 6:12am

VAR is a calculator function, try looking for in skartisitref.pdf (ADE Skill reference) or calculator/wavescan userguides.

I haven't oceaned for a while, but i seem to recall using desVAR does the same thing ?

Title: Re: Cadence Corner Analysis Tool
Post by Andrew Beckett on Feb 22^nd, 2007, 12:05pm

No, desVar() would not be used inside an expression like this. desVar() is for setting and retrieving design variables in OCEAN. VAR() is for accessing the value of a design variable (or swept design variable) in an output expression in a parametric or corner sweep.

Regards,

Andrew.