Patent · US Expired

Method and apparatus for soft defect detection in a memory

US6590818B1 · kind B1 · utility

8Cited by
7References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 17, 2002
Grant dateJul 8, 2003
Priority date
Expiry dateJun 17, 2022

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C2029/1204
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method and apparatus for soft defect detection in a memory is disclosed. Bit lines are conditioned to predetermined voltages which ensure that, upon activation of the corresponding word line, all the storage transistors within the corresponding bit cells (at the intersection of the bit lines and the word line) are electrically conductive. A change in state of the bit cell in response to activation of the corresponding word line indicates the presence of a soft defect. An evaluator coupled to the memory may be used to identify defective memories by comparing the results of the testing to determine if any bit cells changed states. In one embodiment, the conditioning of the bit lines includes charging a bit line to a first predetermined voltage and its corresponding complementary bit line to a second predetermined voltage and then connecting the bit line and complementary bit line together to equalize the voltages.

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