Prediction and reduction of routing congestion

ABSTRACT

Routing congestion is a critical issue in deep submicron design technology and it becomes one of the most challenging problems in today's design flow. This paper presents a true probabilistic congestion prediction method based on router's intelligence to be used in the placement stage of physical design flow. Experimental results show that for IBM-PLACE benchmarks, our prediction algorithm estimates the congestion more accurately than a recent method by about 19%. Furthermore, a new congestion reduction algorithm is presented which is based on contour plotting. Our experiments show that our algorithm reduces congestion by about 28% on average. In addition, comparing our results with a recent approach shows that our reduction technique reduces congestion more by about 13%.

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INDEX TERMS

Primary Classification:
  B. Hardware
  B.7 INTEGRATED CIRCUITS
      B.7.2 Design Aids
          Subjects: Layout

Additional Classification:
  B. Hardware
  B.7 INTEGRATED CIRCUITS
      B.7.2 Design Aids
          Subjects: Placement and routing

General Terms:
Algorithms, Design, Experimentation

Keywords:
congestion, physical design, placement, routability