Synopsys .lib format has been the de facto library format standard for almost a decade. Other attempts to oust it, most notably Accellera's ALF project, have failed to gain widespread acceptance.

Now, Magma and Cadence have issued a joint press release in which Magma is endorsing Cadence's effective current source model (ECSM) as the most accurate timing model and the "timing model of choice" for Magma's Blast Fusion tool.

Cadence and Magma claim the ECSM model, which is used by Cadence's Get2Chip synthesis tool, is more accurate than Synopsys traditional timing model, NLDM (nonlinear delay model), and even the new SPDM (scalable polynomial delay model), which Synopsys is proposing as its next generation timing model within .lib.

Magma and Cadence claim that ECSM improves delay calculation accuracy by modeling a cell's output drive as a current source rather than a voltage source, as is the case with .lib timing models. Current sources, claim the companies, are more effective at tracking non-linear transistor switching behavior and permit highly accurate modeling of long complex interconnects, common in many of today's largest nanometer, low-power designs.

The companies also claim that .lib represents delay as either a NLDM 2D table or a SPDM polynomial equation, and does not provide the level of accuracy demanded at nanometer geometries.

The companies claim the models begin to break down at 130 nanometers and are especially problematic at 90- and 65- nm.

Synopsys to date has held the number one spot in logic synthesis and static timing due largely in part to the correlation between those two tools via the mutual use of the .lib format.

The wide adoption of a new format would seemingly allow another vendor to establish a static timing de facto standard and perhaps logic synthesis standard.

Cadence and Magma claim ECSM already has momentum, as library support is already available from major IP vendors, and both Cadence and Magma provide characterization software to generate ECSM library data.

Cadence and Magma also said they worked together to ensure that ECSM can be combined with existing delay models into a single format.

This enables customers to use the power of ECSM while maintaining a consistent set of timing views that support legacy flows.

The announcement from Cadence and Magma, which is newly in a legal tusslewith Synopsys, comes just days before Synopsys' Interoperability forum, in which Synopsys discusses with customers and partners its progress on developing formats and improving tools.

Cadence and Magma representatives have teamed up to make the case for ECSM in an EDA Views column located at EEdesign.