SAN FRANCISCO Six companies, including Cadence Design Systems Inc. and ARM Holdings plc, have banded together with the aim of accelerating the creation of a standard statistical analysis library format under the Open Modeling Coalition of the Silicon Integration Initiative (Si2).
According to the group, which also includes Magma Design Automation Inc., Extreme DA, Virage Logic Corp. and Altos Design Automation, the open statistical library format will be based on Liberty and current source models, building on an Effective Current Source Modeling 2.1 standard announced by the Silicon Integration Initiative (Si2) Monday (July 24).
Si2 (Austin, Texas) released version 2.1 of the ECSM specification, which includes dynamic power analysis power extensions said to enable power and dynamic power grid analysis information to be passed from cell characterization to design tools enabling them to perform accurate power predictions for nanometer design.
The intent of the collaboration is to enable interoperability between design tools and methodologies for 65-nanometer design and below, and to create a comprehensive solution that will eliminate the need for designers to support multiple library formats, according to the companies involved.
"Si2 welcomes the collaboration of these industry leaders in statistical static timing analysis with ARM and Virage in producing an open, industry-managed format to enable statistical analysis of design variability. Choosing to do so within the Open Modeling Coalition underscores the importance of Si2's efforts to the industry," said Steve Schulz, Si2's president and CEO, in a statement.
Statistical analysis is considered necessary to enable designers to more efficiently manage the increasing process variations in manufacturing and sensitivity to operating-environment parameters that affect circuit performance at 65-nm and below. Standardization of the information required to support this analysis is key to rapid industry adoption, according to Si2.
The format being developed by the companies will be contributed to the Open Modeling Coalition (OMC) in response to Si2's request for technology. This contribution will be considered for standardization in the OMC for a statistical static library format, Si2 said.
Conspicuously absent from the collaboration is Synopsys Inc., which Monday added statistical analysis to its popular PrimeTime signoff solution. Synopsys released its composite current-source (CCS) model, an extension to the open source Liberty, in 2004. The CCS model is considered a rival to the ECSM model, which has been pushed by Cadence since 2001.
"The ECSM-based approach is incomplete because it does not fully address the modeling issues required for a variation-aware design solution," said Bijan Kiani, vice president of marketing for Synopsys' implementation group, in an email Tuesday. "A complete variation-aware solution needs to model device and interconnect variation. Synopsys will soon be adding extensions to Liberty and to the Standard Parasitic Exchange Format to enable a comprehensive variation-aware design flow."
Si2 said the power extensions in ECSM 2.1 are compatible with existing ECSM and Liberty constructs, enabling ease of extraction by tools that correctly parse Liberty models, and to provide efficient representation to control the amount of data. The ECSM power extension format has been optimized to provide an efficient storage medium for dynamic cell behavior and appropriate reductions are performed on the waveforms to provide a user-specified level of accuracy, Si2 said. The controls provided to adjust the accuracy enable a compromise between the computational time and accuracy of the analysis and the size of the model, according to the organization.
Also Monday, Si2 and the Spirit Consortium announced a strategic partnership and cross-membership agreement to facilitate tighter collaboration designed to improve the productivity of the total system-on-chip (SoC) design flow. The two organizations said they will work together to coordinate technical roadmaps, targeting consistency of data shared among OpenAccess and Open Modeling efforts provided by Si2 and IP-XACT specifications provided by The Spirit Consortium. The organizations will also coordinate an integrated architecture that takes advantage of the highly complementary technology offerings, they said.
At a heavily attended meeting here Monday, the Spirit Consortium announced that it has been incorporated in California as a non-profit mutual benefit corporation. The organization, which was originally envisioned in 2003 to last for only two years, has decided to stick around to provide further technical specifications to help the industry integrate multi-vendor design-flows. The Spirit Consortium also unveiled a new logo and said it has changed the name of its specification to IP-XACT.