Export of Switch Function and Isolation Enable Condition Expressions

In a Liberty Power Model export, it is important to export the derivation or knowledge to interpret switch_function and isolation_enable_condition expressions to ensure that you are able to perform the following tasks:

Correlate the generated expressions with a schematic.
Establish the accuracy of the generated expressions and design intent.

You can register the names of virtual supply nets that need the switch_function derivation by using the following option in a setup file.

virtualSuppliesForSwitchFunctionDerivation "VVDD VVDD_CPU VVDD_LDO"

You can register the names of the data port names that need the isolation_enable_condition derivation by using the following option in a setup file.

signalPortsForIsoEnableConditionDerivation "OUT OUT2 IN1"

Regular expressions for virtual supply and port names is supported. The step-by-step derivation of switch_functions for registered virtual supply nets and isolation_enable_conditions for registered data ports appear in the CIW and in the extractor log file. However, this information is shown only if the pg_pin or data pin is included in a Liberty model.

Alternatively, you can use the environment variables to export the derivations.

Virtuoso Power Manager User Guide
Product Version IC23.1, June 2023