Incremental Path-Based Timing Analysis for IC Place and Route
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current timing analysis methods in integrated circuit design, such as static timing analysis (STA), are conservative and introduce pessimism, leading to increased power consumption, area, and reduced speed due to their inability to accurately account for process variations, necessitating a more accurate path-based timing analysis (PBA) for optimization.
Innovation Solution
Incorporating an incremental path-based analysis (PBA) into the place and route optimization process, which reduces elapsed time and allows for more accurate timing optimization by analyzing specific paths rather than relying on conservative graph-based analysis (GBA) results, enabling faster speed, lower power consumption, and smaller area with minimal memory and CPU overhead.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If graph-based timing analysis (GBA) is used for timing verification, then computational speed is fast, but timing accuracy deteriorates due to conservatism and pessimism
Solution Approach 1:
The patent segments the timing analysis process into two distinct phases: (1) GBA is used for initial fast verification to identify potential timing issues, and (2) PBA is applied specifically to the identified critical paths for accurate timing optimization. This segmentation allows the system to leverage the speed of GBA while obtaining the accuracy of PBA only where needed, resolving the contradiction between computational speed and timing accuracy.
2Measurement precision
If path-based timing analysis (PBA) is used for accurate timing optimization, then timing accuracy is improved, but elapsed time increases significantly
Solution Approach 1:
The patent applies preliminary action by using GBA first to pre-identify critical paths and potential timing violations before applying PBA. This preliminary filtering step ensures that PBA is executed only on the necessary subset of paths rather than all possible paths, dramatically reducing the elapsed time while maintaining timing accuracy for the critical optimization targets.
3Reliability
If conservative timing analysis is used to ensure timing compliance, then reliability is improved, but power consumption and area increase
Solution Approach 1:
The patent changes the analysis parameter from conservative GBA estimates to accurate PBA measurements on critical paths. By using PBA to obtain precise timing values, the optimization process can confidently reduce safety margins and conservatism, leading to optimized circuit designs that consume less power and occupy smaller area while maintaining timing compliance through accurate rather than conservative analysis.
Data Source
AI summary
A graph-based analysis (GBA) output is obtained comprising timing information pertaining to a plurality of paths in an integrated circuit. A path-based analysis (PBA) is performed on the GBA output to analyze timing of the plurality of paths and generate a set of improved timing results; wherein the physical measurements used by the PBA are more accurate than the physical measurements used by the GBA. The PBA result is output to an optimizer to automatically adjust the circuit.