Patent · US Expired

Placement method for integrated circuit design using topo-clustering

US6961916B2 · kind B2 · utility

27Cited by
30References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 1, 2002
Grant dateNov 1, 2005
Priority date
Expiry dateMay 1, 2022

Classification

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

Abstract

The present invention, generally speaking, provides a placement method for the physical design of integrated circuits in which natural topological feature clusters (topo-clusters) are discovered and exploited during the placement process. Topo-clusters may be formed based on various criteria including, for example, functional similarity, proximity (in terms of number of nets), and genus. Genus refers to a representation of a netlist in terms of a number of planar netlists—netlists in which no crossing of nets occurs. Topo-clusters drive initial placement, with all of the gates of a topo-cluster being placed initially in a single bin of the placement layout or within a group of positionally-related bins. The portion of a topo-cluster placed within a given bin is called a quanto-cluster. An iterative placement refinement process then follows, using a technique referred to herein as Geometrically-Bounded FM (GBFM), and in particular Dual GBFM. In GBFM, FM is applied on a local basis to windows encompassing some number of bins. From iteration to iteration, windows may shift position and vary in size. When a region bounded by a window meets a specified cost threshold in terms of a speci…

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