Design-Rule-Aware Congestion Model with Explicit Modeling of Vias and Local Pin Access Paths

As technology advances, there is a large gap between traditional congestion model used in global routing and routing resource consumption in detailed routing. The new factors contributing to congestion include local pin access paths, vias, and various design rules. In this paper, we propose a practical congestion model with measurement of the impact of design rules, and resources consumed by vias and local pin access paths. This congestion model is compatible with path search algorithms used in global routing. Validated by experiments using full-flow routing, this congestion model correlates better with real resource consumption situation in detailed routing. Compared with previous work, it leads to much better solution quality and shorter runtime of detailed routing when it is used in layer assignment phase of global routing stage.