| 摘要 |
A defect management engine (DME) for memories integrates a plurality of redundancy data cells and a plurality of redundancy address cells in the same array. The redundancy data cells are used for replacing defective cells in the memories. The redundancy address cells store the addresses of the defective cells. The memories are preferably sub-divided into a plurality of domains. A plurality of defective cells in each domain are supported by a plurality of repair units, each consisting of one or more redundancy data bits and redundancy address bits in the DME. When one or more data bits are read from a domain in the memory, the corresponding wordline in the DME simultaneously activates a plurality of repair units coupling to the wordline (self-contained domain selection). The redundancy data bits and the redundancy address bits are also read from the redundancy data cells and redundancy address cells, respectively. The DME logic detects whether or not the redundancy address bits match or do not match the address inputs of each repair unit (self contained redundancy match detection). This couples either redundancy data bits from the DME (i.e., a matching condition) or the data bits from the domain in the memories (i.e., a no match condition) to the corresponding DQ (self-contained redundancy replacement). The DME enables an integrated redundancy means (self-contained domain selection, self-contained redundancy match detection, and self-contained redundancy replacement). Single bit replacement, multi-bit replacement, line replacement, and variable bit size replacement are discussed. Finally, an extension of the DME concept to a memory system is also discussed.
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