Congestion minimization during placement without estimation

TitleCongestion minimization during placement without estimation
Publication TypeConference Paper
Year of Publication2002
AuthorsHu, B, Marek-Sadowska, M
Conference NameComputer Aided Design, 2002. ICCAD 2002. IEEE/ACM International Conference on
Date Publishednov.
Keywordsbounding box placers, circuit layout CAD, circuit optimisation, congestion minimization techniques, cost function optimization, Dragon routability-driven placer, estimate-then-eliminate strategies, estimation-less placement, global nets, implicit white space allocation, integrated circuit layout, integrated circuit modelling, local nets, logic CAD, Rent rule, routing resource usage, SPARSE routability, standard cell global placement, total wire length guided placers
AbstractThis paper presents a new congestion minimization technique for standard cell global placement. The most distinct feature of this approach is that it does not follow the traditional "estimate-then-eliminate" strategy. Instead, it avoids the excessive usage of routing resources by "local" nets, so that more routing resources are available for the uncertain "global" nets. The experimental results show that our new technique, SPARSE, achieves better routability than the traditional total wire length (bounding box) guided placers, which had been shown to deliver the best routability results among the placers optimizing different cost functions. Another feature of SPARSE is the capability of allocating white space implicitly. SPARSE exploits the well known empirical Rent's rule and is able to improve the routability even more in the presence of white space. Compared to the most recent academic routability-driven placer, Dragon, SPARSE is able to produce solutions with equal or better routability.