Semiconductor memory device and method of operating semiconductor memory device

Abstract

A semiconductor memory device includes a plurality of memory cells partitioned into a plurality of row blocks that are each associated with at least one respective row block identity bit within a portion of a row address. A row decoder is provided, which includes a repair controller having a plurality of fuse boxes therein that correspond to respective ones of the plurality of row blocks and include a first fuse box configured to store a first defective address. The repair controller is configured to: (i) activate a first redundancy word-line, which replaces a first defective word-line designated by the first defective address, in response to comparing a first access address with the first defective address output from the first fuse box, during a first mode, and (ii) activate a second redundancy word-line, which replaces a first edge word-line designated by the first access address, in response to comparing the first access address with a first reset address output from the first fuse box, during a second mode.