MLDB Libraries

Power Manager processes the Liberty files to read the standard cell, special cell, and macro cell model definitions and stores them in an OpenAccess-based proprietary database. This avoids the need to reprocess the Liberty files every time a command is executed. Such a database is called Model Library database (MLDB). MLDB reads and stores the PG pins, pins, and the non-characterized attributes for the various cell models provided through Liberty files. These attributes are saved in a different library than the design or PDK library, which can be utilized in various projects to extract details instead of parsing the Liberty files every time. This can save a lot of run time that is required to parse large Liberty files if it has to be done repeatedly for extracting power-related attributes. If no user-specified library is provided, the database is in-memory and can be used only for a particular Virtuoso session.

MLDB creation requires a new library to be created. The library includes a tech.db file, which contains all the power-related attribute information that is extracted by a single traversal from the registered Liberty files. The setup registration for MLDB is:

projectMldbLibName "MLDB_TESTCELL"

A new .lib file is added to MLDB only in one of the following conditions:

• You have re-imported a modified setup specifying additional .lib files and removed .lib files that are not required anymore.
• You have run a VPM command, such as extract power intent or import power intent.

The modified MLDB is saved when closing all the files or exiting Virtuoso.

Related Topics

Registering Libraries

Special Cell and Standard Cell Modeling

Design Sub-Block Modeling During Top-Level 1801 Design Model Extraction

Reference Libraries or Cells