Patent · US Expired

Cell placement representation and transposition for integrated circuit physical design automation system

US6155725A · kind A · utility

131Cited by
30References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 19, 1994
Grant dateDec 5, 2000
Priority date
Expiry dateApr 19, 2014

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F30/392
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A large number of possible cell placements for an integrated circuit chip are evaluated to determine which has the highest fitness in accordance with a predetermined criteria such as interconnect congestion. Each cell placement, which constitutes an individual permutation of cells from a population of possible permutations, is represented as an initial cell placement in combination with a list of individual cell transpositions or swaps by which the cell placement can be derived from the initial cell placement. A cell placement can be genetically mutated and/or inverted by adding swaps to the list for its cell placement which designates cells to be transposed. Genetic crossover can be performed by transposing swaps between the lists for two cell placements. This cell representation and transposition method enables any type of cell transposition to be performed without loss or duplication of cells or generation of illegal placements.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.