| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a semiconductor memory device comprising a redundancy circuit that minimizes the circuit area, while improving the redundancy efficiency. <P>SOLUTION: The redundancy circuit includes a sector selector and a bit-line selector. The bit-line selector saves defective bit lines, and the bit-line selector saves defective global bit lines to selectively save the defective bit lines. The sector selector includes a fixed address cell storage box for storing the address of the defective bit lines and a flexible address cell storage box for storing the address of the defective global bit lines. The flexible address cell storage box includes a precharge unit, a coding unit, programming units and selection units. The coding unit has a programmable memory cells therein and programs the programmable memory cells, in response to the address of the defective bit line. The selecting units generates a redundancy signal, in response to the address of the defective global bit line and a fuse open signal that determines the mode of operation propriety of the flexible address cell storage box. <P>COPYRIGHT: (C)2004,JPO</p> |
