How to automatically store technology version on instance in schematics and layout?

Hi,

I'd like to store the version number of the PDK on an instance when this instance is instantiated in schematic or layout. I need this in order to be able to check with which version of the PDK a particular design has been made. Later, I will create a script that hierarchically checks all instances of a given design, and reports the used versions. This will then be a script run at tape-out to ensure all devices are generated with the correct (latest) PDK version.

It could be done by adding a parameter with the version number as value to the CDF, like this:

However, if the PDK gets updated, the version number will be increased, which would mean, with this implementation, that the CDF of all cells in the library have to be updated to the new version. Of course, this could be automated, but i would like to use a different approach.

The version of the PDK which is loaded in Virtuoso is stored in an environment variable called TECH_VERSION. It can be retrieved by doing:

What I would like to happen is that when the instance is instantiated, the value of TECH_VERSION is automatically stored in the CDF parameter PDK_version. Something like this doesn't work:

This would simply put the text "getShellEnvVar( "TECH_VERSION" )" as value in the "PDK_version" field.

An other solution could be by putting some code in a call-back procedure that puts the version number in the parameter value. However, this only works when this call-back procedure is triggered. If a default device is instantiated, with no modifications to its parameters, the call-back will not be triggered, thus the version number will not be set.

So, I think this has to be a post-instantiation trigger. And I don't know how to do that properly. Any help is highly appreciated.

If an other solution is possible, I would surely like to know that as well.

Thanks in advance.

With kind regards,

Sjoerd