Integrated Circuit Timing Signoff via Path Derating

The patent applies preliminary action by calculating path derating factors before final timing signoff. The methodology performs preliminary timing analysis that accounts for voltage drops and on-chip variations, establishing derating factors that are then applied in the final signoff analysis. This ensures timing risks are identified and addressed before the design is finalized, preventing timing failures without requiring complete redesign.

The patent applies parameter changes by introducing voltage drop considerations and on-chip variation parameters into the timing analysis. Instead of using only nominal voltage values, the methodology modifies the analysis parameters to include actual voltage drops along signal paths and statistical variations in transistor characteristics. This transforms the timing analysis from a simple nominal-value check to a comprehensive parameter-based assessment that captures real-world behavior.

The patent applies segmentation by dividing the IC design into multiple signal paths and calculating timing characteristics for each path separately. The methodology segments the complex design into manageable path-level analyses, where voltage drops and on-chip variations are evaluated for individual paths rather than the entire design at once. This segmentation enables precise timing analysis while keeping computational complexity tractable through systematic decomposition.

The patent applies parameter changes by transforming the timing analysis from using fixed nominal values to using statistically-derived parameters that account for on-chip variations. The methodology calculates mean and standard deviation parameters for timing characteristics based on transistor variation data, then uses these statistical parameters to determine timing signoff values. This parameter transformation improves measurement precision by capturing real-world variability while maintaining analytical tractability through statistical methods.

The patent applies preliminary action by calculating path derating factors during the timing analysis phase, before final design signoff. The methodology performs preliminary calculations of voltage drops and timing gaps, establishes derating factors, and then applies these factors in the final evaluation. This preliminary establishment of derating factors avoids the need for iterative recalculations during signoff, reducing overall design cycle time while maintaining high evaluation accuracy.

The patent applies parameter changes by transforming raw timing gap measurements into normalized derating factor parameters. The methodology calculates timing gaps between arrival and required times, then converts these gaps into derating factors that can be directly applied to timing signoff analysis. This parameter transformation condenses complex timing gap information into actionable derating parameters, improving design evaluation accuracy while streamlining the calculation process for practical implementation.