Techniques for scalable and effective routability evaluation

摘要: Routing congestion has become a critical layout challenge in nanoscale circuits since it is factor determining the routability of design. An unroutable design not useful even though closes on all other metrics. Fast closure can only be achieved by accurately evaluating whether routable or early cycle. Lately, common to use “light mode” version global router quickly evaluate given placement. This approach suffers from three weaknesses: (i) does adequately model local routing resources, which cause incorrect predictions that are detected late, during detailed routing; (ii) maps obtained tend have isolated hotspots surrounded noncongested spots, called “noisy hotspots”, further affects accuracy evaluation; and (iii) metrics used represent may yield numbers do provide sufficient intuition designer, moreover, they often fail predict accurately. article presents solutions these issues. First, we propose approaches resources. Second, smoothing technique reduce number noisy obtain more accurate evaluation result. Finally, develop new metric represents with higher fidelity. We apply proposed techniques several industrial demonstrate one better mitigation tools perform much improve routability.