MSIM Spice Circuit Simulator Runs 10X Faster for Characterizing CCS Model

Legend Design Technology, Inc. announced that its MSIM, a high-accuracy Spice circuit simulator, has been upgraded for efficient characterization of CCS (Composite Current Source) model used in cell library characterization in SoC designs. MSIM with ‘Advanced CCS Control’ runs 5X~10X faster than most popular Spice simulators, when characterizing CCS Timing Model under PrimeTime accuracy requirement. MSIM provides the benefits of extreme accuracy, high speed, excellent convergence, built-in RC reduction, and best price-performance.

To produce CCS model, the output current will be simulated for each pair of input slew-rate and output load. Due to the inaccuracy from Spice simulations, there will always be a difference between voltage supply and the integral of current waveform divided by output load. If that difference exceeds 5% of voltage supply, PrimeTime will issue a warning for possible inaccuracy in full-chip static timing analysis.

To meet PrimeTime accuracy requirement, Spice simulation at fast input slew-rate and small output load shall need much tighter tolerances for simulation controls, which could increase the run time significantly. However, for most slew-rates and loads in the table, it becomes unnecessary to apply those tighter tolerances for corresponding simulation jobs.

With extensive field experiences and R&D efforts, we have successfully developed the solutions for the above challenges and built the ‘Advanced CCS Control’ into MSIM simulator for characterizing CCS models efficiently. MSIM with ‘Advanced CCS Control’ can automatically optimize the simulation tolerances and time-step controls for various input slew-rates and output loads.

“For our CCS model characterization of standard cell library, MSIM with ‘Advanced CCS Control’ has provided us an excellent balance between accuracy and speed. MSIM will ensure the CCS modeling accuracy within PrimeTime requirement,” said Kenny Tung, Corporate Library Lead, Applied Micro Circuits Corporation.

MSIM circuit simulator with ‘Advanced CCS Control’ is immediately available. At DAC 2008 in Anaheim, California, Legend will be demonstrating MSIM, Turbo-MSIM, CharFlo-Cell! and CharFlo-Memory! at Booth #1733.

About Legend
Legend Design Technology Inc. is a leading provider of circuit simulation and semiconductor IP library characterization software for SoC designs. With an emphasis on productivity and value, Legend’s library characterization toolset, CharFlo-Memory! for memory IP and CharFlo-Cell! for standard cell and IO library, revolutionize the time-consuming and error-prone processes associated with characterization. MSIM is Legend’s high-accuracy SPICE circuit simulator with fast speed and great convergence. Turbo-MSIM is Legend’s full-chip Fast-Spice simulator ideal for timing and power simulation, and mixed-signal circuit verification. Both simulators are well designed for nanometer technology and provide excellent price performance.

PrimeTime is a registered trademark of Synopsys, Inc.