| 摘要 |
PROBLEM TO BE SOLVED: To provide a memory device including a means coupling plural data storing cells, at least one redundant data storing cell, a redundant match detecting circuit, and a programmable fuse to a redundant match detecting circuit. SOLUTION: When a redundant match detecting circuit detects the prescribed condition set by a programmable fuse, a defective data is replaced by one redundant data storage region. Decoding is achieved by selecting an (e) fuse to be cut off by a data bus. Data bus, also, reads a state of the (e) fuse, and is used for guaranteeing that the (e) fuse is correctly cut off. Electric power is applied effectively to a selected (e) fuse while the data bus is shared to decode and verify the (e) fuse. Time-muliplex is used for transfer operation to reduce the number of communication channels between the (e) fuse and the redundant match detecting circuit, and transferring successively (e) fuse information to the redundant match detecting circuit can be performed. Actual time-multiplex operation for performing transfer is preferable to make 'enable' only after a chip is made a power source apply state.
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