Patent · US Expired

Fault-tolerant memory array

US4768169A · kind A · utility

12Cited by
5References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 28, 1983
Grant dateAug 30, 1988
Priority date
Expiry dateOct 28, 2003

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F11/187
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A memory array is organized into rows and columns of memory cells, each cell having a configuration which passes current or blocks current depending upon the state of that cell. The array includes sense circuits to sense cell state. In a preferred embodiment of the invention, an address signal sent to the memory array activates two sets of memory cells connected to the same sense lines, and the threshold level of the sense circuits is set above the level which would be sensed for a failed bit, so that a failed bit appears as if unprogrammed or erased. Because each bit is represented by a pair of memory cells, a failed cell in a pair will not affect operation of the functioning cell in the pair or result in error.

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