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Characterizing mixed-signal macros to create instance-specific models for timing, power, and noise can be a challenging task. The Cadence characterization portfolio offers Liberate AMS, a mixed-signal characterization solution that enables you to take care of your characterization needs.
You can perform characterization with Liberate AMS either from the command line or the Virtuoso GUI as talked about in the Exploring Intuitive Means to Characterize Large Mixed-Signal Blocks blog. This blog covers the Liberate AMS command-line flow and a related Rapid Adoption Kit (RAK) that helps you understand this flow.
The following diagram depicts the Liberate AMS command-line flow:
As shown in this diagram, the Liberate AMS control files amschar.tcl and template.tcl, along with the netlist and model files, are passed to the tool. Using these inputs, Liberate AMS has two methods for characterizing a block:
In both the flows, the tool operates in a server-client model. The server decides which arcs must be characterized and then passes these arcs to the clients for characterization by Spectre APS. After the characterization is complete, the server gathers the results from the clients and places them in a database called the LDB (Liberate DataBase), from which different Liberty file formats (NLDM, CCS, and so on) can be written.
Liberate AMS: Command Line Flow (RAK)
This RAK demonstrates the capabilities of Liberate AMS using various examples. Characterization flow of six different IP blocks is covered in the following sections of this RAK:
Each section provides detailed information on the operation of the IP blocks using top-level Virtuoso testbenches and the simulation requirements to verify if the design is working as expected. Which all arcs must be characterized and the required Liberate AMS setup is also explained. Then the steps to run the characterization and analysis of the output files is also well covered.
In addition to demonstrating the use of the command-line flow for IP blocks, the RAK also includes an appendix covering the following information:
This is just a summary of the information covered in the RAK; for detailed information check out the RAK on the Cadence Support portal .
For more information about working with the Liberate Variety statistical characterization solution, see the following documents:
Library Characterization Tidbits is a blog series aimed at providing insight into the useful software and documentation enhancements in the LIBERATE release. In addition, this series would broadcast the voices of different bloggers and experts, who would share their knowledge and experience about all the tools in Liberate Characterization Portfolio. To receive notifications about the new blogs in this series, click Subscribe and submit your email ID in the Subscriptions box.