Patent · US Expired

Method and apparatus for horizontal congestion removal

US6123736A · kind A · utility

86Cited by
16References
44Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 6, 1997
Grant dateSep 26, 2000
Priority date
Expiry dateAug 6, 2017

Classification

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

Abstract

Integrated circuit chips (IC's) require proper placement of many cells (groups of circuit components) and complex routing of wires to connect the pins of the cells. Because of the large number of the cells and the complex connections required, it is essential that placement of the cell and the wire routine be done correctly to avoid any congestion of wires. Placement of the cells and the routing of the wires to avoid congestion can be accomplished by determining congestion of various regions, or pieces, of the IC's after an initial placement of the cells and routing of the wires. The present invention discloses a method and apparatus to define the regions, or pieces, of the IC, determine various density measurement of the pieces, and adjust the sizes of the pieces to reduce congestion of congested pieces by reallocating space from uncongested pieces to congested pieces. In addition, the present invention discloses the technique of adjusting the sizes of the piece to minimize disturbing the placement and wire routing while the congestion is being reduced. This is accomplished by comparing the vertical location of each of the pieces to the vertical location of the pieces next to it.

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