Device for repairing a Semiconductor memory
US6571352B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Feb 28, 2001 |
| Grant date | May 27, 2003 |
| Priority date | — |
| Expiry date | Jun 8, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C29/846
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A block repair device is used in a Dynamic Random Access Memory (DRAM) having a primary array with a defective cell and a redundant array with a redundant row. The block repair device includes a set of fuses, anti-fuses, or flash EEPROM cells that store a block repair configuration that determines the dimensions (e.g., the number of rows and columns spanned) of a repair block used to repair the defective cell. Routing circuitry, such as mux circuitry, in the block repair device is configured by the stored block repair configuration to output some row and column address bits from received row and column addresses in a selected ratio. Comparison circuitry in the block repair device then compares the row and column address bits output by the routing circuitry with a stored portion of the address of the defective cell that defines the repair block. When a match occurs, the comparison circuitry implements a block repair by activating the redundant row and by causing data to be written to or read from the activated redundant row instead of the primary array.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.