A diagnostic method for detecting and assessing the impact of physical design optimizations on routing

ABSTRACT

In this paper, we describe a method to independently audit a physical design to identify inefficiencies detrimental to high quality routing. The method provides an exhaustive review of netlist structures having many possible equivalent solutions, such as buffer trees, as well as other structures with flexibility of implementation. In addition, the method provides a means to quantify the inefficiency, in terms of routing length and the impact to routing congestion. Lastly, the method gives physical design engineers a framework to quickly identify causes of routing congestion and identify structures that can be acted upon to enhance routing.

REFERENCES

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INDEX TERMS

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

Additional Classification:
  J. Computer Applications
  J.6 COMPUTER-AIDED ENGINEERING
      Subjects: Computer-aided design (CAD)

General Terms:
Algorithms, Design, Measurement

Keywords:
efficiency, netlist, physical synthesis, placement, routing, timing