Stats

Locked Locked
Replies 2
Subscribers 126
Views 4235
Members are here 0

This discussion has been locked.

You can no longer post new replies to this discussion. If you have a question you can start a new discussion

When setting temperature as a design/global variable, it is called an unknown parameter and a simulation error occurs

I'm trying to simulate a PTAT current source in a transient analysis (where the temperature coefficient on a ipwl does not do anything). However, after making temperature a variable in this current source's expression and setting it as a design variable in Maestro, I get a simulation error stating it is an unknown parameter:

Error found by spectre during hierarchy flattening.
ERROR (SFE-1997): "netlist" 1403: Cannot run the simulation because I0: parameter `wave': Unknown parameter `temperature' has been specified in expression `((500e-09)+(temperature-27)*(1.687759e-09))', correct the expression and rerun the simulation.

I am running sub-version ICADVM20.1-64b.500.27.EHF11760.

ShawnLogan over 2 years ago

Dear jackrc11,

jackrc11 said:
However, after making temperature a variable in this current source's expression and setting it as a design variable in Maestro, I get a simulation error stating it is an unknown parameter:

I believe you need to refer to the simulation temperature in your expression as VAR("temp") in lieu of your design variable "temperature". This is a frequent point of confusion so you are not alone! There is a recently published On-line support Troubleshooting article that attempts to clarify the proper syntax to use when referring to the simulation temperature and the nominal temperature in expressions and models at URL:

https://support.cadence.com/apex/ArticleAttachmentPortal?id=a1O3w000009xxe7EAA&pageName=ArticleContent

Have you tried replacing your use of "temperature" in your expressions with VAR("temp")?

Shawn
Cancel
Vote Up 0 Vote Down

Cancel
Andrew Beckett over 2 years ago in reply to ShawnLogan

Actually, if it's an expression on a spectre isource then it becomes a bsource and so you should use "temp" to refer to the in-simulation temperature. VAR("temp") is for output expressions in the ADE output pane (for example).

Andrew
Cancel
Vote Up 0 Vote Down

Cancel

Community Guidelines

The Cadence Design Communities support Cadence users and technologists interacting to exchange ideas, news, technical information, and best practices to solve problems and get the most from Cadence technology. The community is open to everyone, and to provide the most value, we require participants to follow our Community Guidelines that facilitate a quality exchange of ideas and information. By accessing, contributing, using or downloading any materials from the site, you agree to be bound by the full Community Guidelines.