Patent · US Expired

Apparatus and method for detecting over-programming condition in multistate memory device

US5771346A · kind A · utility

77Cited by
9References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 24, 1996
Grant dateJun 23, 1998
Priority date
Expiry dateOct 24, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C2211/5643
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

An apparatus and method for detecting an over-programming condition in a multistate memory cell. The invention is also directed to identifying the over-programmed cells and providing an alternate location at which to write the data intended for the over-programmed cell. An over-programmed state detection circuit generates an error signal when the data contained in a multistate memory cell is found to be over-programmed relative to its intended programming (threshold voltage level) state. Upon detection of an over-programmed cell, the programming operation of the memory system is modified to discontinue further programming attempts on the cell. The over-programmed state detection circuit is also used to assist in correcting for the over-programming state, permitting the programming error to be compensated for by the memory system.

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