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Simulators >> Circuit Simulators >> Problem in Using Protected modelcard in Cadence
https://designers-guide.org/forum/YaBB.pl?num=1245321469

Message started by cmos.analogvala on Jun 18^th, 2009, 3:37am

Title: Problem in Using Protected modelcard in Cadence
Post by cmos.analogvala on Jun 18^th, 2009, 3:37am

We have received modelcard for mismatch analysis for some technology from foundary. However these model files are proected. The model card includes \pragma statements.
When I include these model files in ADE with and run silulation it gives following error.

"Error found in protected block by virtuso spectre"

However the same model files run successfully for tt corner/section.

Please help

-CA

Title: Re: Problem in Using Protected modelcard in Cadence
Post by Andrew Beckett on Jul 10^th, 2009, 6:30am

Did you include the model file (from Setup->Model Libraries) without specifying a section, and it's expecting a section name? Just a guess...

To be honest, you really need to talk to the provider of the model file. Spectre intentionally gives limited information about errors within protected blocks, because otherwise crafty people can determine info about the contents by intentionally using them inappropriately and forcing the simulator to generate errors. Unfortunately that's not terribly helpful when you've genuinely made a mistake and aren't sure what it is!

Regards,

Andrew.

Title: Re: Problem in Using Protected modelcard in Cadence
Post by cmos.analogvala on Jul 13^th, 2009, 7:25pm

Yes the problem was very much on the same line . .
The montecarlo model card that I am using, requires a design variable called "sigma" to be set to 1,2 or 3. Otherwise it gives the above mentioned error ....

Thanks a lot for the reply ...

-CA

Title: Re: Problem in Using Protected modelcard in Cadence
Post by In Tao on Jan 4^th, 2010, 9:47pm

hi I encountered the same problem with the same error message.
"Error found in protected block by virtuso spectre"
Cmos.analogvala mentioned that it was solved by setting the sigma varibale. However, I don't know where to set this variable?
please help me.
very thanks!

Title: Re: Problem in Using Protected modelcard in Cadence
Post by Andrew Beckett on Jan 5^th, 2010, 2:14am

Well, setting a design variable called sigma will only help if you're using the same model file as Cmos.analogvala . If that's really the case, then in ADE do Variables->Edit and add a new design variable called "sigma" and define the value.

Alternatively it may be that the protected model file requires a section name when the model file is referenced on the Setup->Model Libraries form.

Put another way, there are lots of potential reasons why you would get this error - it's just telling you that there was some sort of error within the protected part of the model file. Because it is protected, spectre doesn't give a great deal of information about the cause, because otherwise you could use spectre to reveal internal information within the protected block, simply by including the file in a way to force errors...

Ultimately you need to consult any documentation provided with the model file (maybe comments at the top of the file?) to see how it is supposed to be used. If that still doesn't solve the problem, you'll need to talk to whoever provided the model file to see if there are any additional requirements.

Regards,

Andrew.