Modeling repeaters explicitly within analytical placement

ABSTRACT

Recent works have shown that scaling causes the number of repeaters to grow rapidly. We demonstrate that this growth leads to massive placement perturbations that break the convergence of today's interleaved placement and repeater insertion flows. We then present two new force models for repeaters targeted towards analytical placement algorithms. Our experiments demonstrate the effectiveness of our repeater modeling technique in preserving placement convergence (often also accompanied by wire-length improvement) at the 45 and 32 nm technology nodes.

REFERENCES

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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, Theory

Keywords:
analytical placement, buffering, force-directed placement, interconnect, placement, repeater insertion, scaling