| 摘要 |
PROBLEM TO BE SOLVED: To provide a redundant circuit efficient in testing and a semiconductor device equipped with it. SOLUTION: When testing to find defective bits, the defective bits are extracted and their addresses are written in electric fuses, then check testing is made to confirm the written addresses. The electric fuses are used for all the redundant circuits, and recovery-impossible signals are outputted when the defective bits are found. Each circuit has multiple fuse-set blocks each having several electric fuses and a fuse selection circuit. When testing to find the defective bits, the fuse selection circuit selects a fuse block to program next and the selected fuse block holds address signals inputted at testing in a register circuit. When the defective bit is found in the testing, the electric fuse in the selected fuse-set block is programmed, and the content of the programmed electric fuse is compared with the address signals stored in the register circuit. COPYRIGHT: (C)2007,JPO&INPIT
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