Patent · US Expired

Method and circuit for error correction in CAM cells

US7350137B2 · kind B2 · utility

6Cited by
11References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 22, 2005
Grant dateMar 25, 2008
Priority date
Expiry dateDec 24, 2025

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C15/00
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method and circuit is provided for detecting and correcting errors in an array of content addressable memory (CAM) cells. The array includes wordlines, searchlines, bitlines, and matchlines for reading from, writing to, and searching CAM cells in the array. The method includes the following steps: a row parity bit corresponding to a parity of a first plurality of bits stored along a row of CAM cells is stored; a column parity bit corresponding to the parity of a second plurality of bits stored along a column of CAM cells is stored; a parity of the first plurality of bits is read and generated and the generated parity is compared to the stored row parity bit, if the generated and stored parity bits do not match, columns of the array are cycled through; a parity of the second plurality of bits is read and generated and the generated parity is compared to the stored column parity bit until a mismatch is indicated; and, a bit located at an intersection of the mismatched row and column is inverted if the mismatch is indicated.

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