Patent · US Expired

Method for balancing a clock tree

US6351840B1 · kind B1 · utility

14Cited by
9References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 9, 1999
Grant dateFeb 26, 2002
Priority date
Expiry dateDec 9, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F1/10
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

In an integrated circuit (IC) design, a set of K×N clocked IC devices (“syncs”) such as flip-flops and latches are organized into K clusters of N syncs each, with each cluster being clocked by a separate clock tree buffer. An improvement to a conventional “K-center” method for assigning syncs to clusters is disclosed. The improved method, which reduces the separation between syncs within the clusters, initially employs the conventional K-center method to preliminarily assign the K×N syncs to K clusters having N syncs per cluster. The improved method thereafter ascertains boundaries of rectangular areas of the IC occupied by the separate clusters. When areas of any group of M>1 clusters overlap, the K-center meth is repeated to reassign the set of M×N syncs included in e M overlapping clusters to a new set of M clusters. The new set of M clusters are less likely to overlap.

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