Redundancy circuit for use in a semiconductor memory device
US4794568A · kind A · utility
33Cited by
2References
19Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 1, 1987 |
| Grant date | Dec 27, 1988 |
| Priority date | — |
| Expiry date | May 1, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C29/785
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A normal decoder and a redundant decoder having address program devices are used for the replacement of bad cells. The number of address program devices is one more than the number of input address bits for selecting a normal row or column. The input signals of the additional program device are complementary to the input signals of one of the other program devices. The program of the program devices have two steps to repair the faulty cells. To increase the reliability of redundancy, a nonvolatile memory element used in the program devices is a bridge connected four cell FLOTOX type nonvolatile memory device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.