SEMICONDUCTOR MEMORY DEVICE AND ITS OPERATION METHOD, ESPECIALLY COMPARING MARINE OF A SENSE AMP

摘要

PURPOSE: A semiconductor memory device and its operation method are provided to increase accuracy of a read operation or a refresh operation and also to improve reliability of the device by increasing a comparison margin of a sense amp. CONSTITUTION: A normal word line block includes a number of normal word lines(NWL) connected to memory cells. A redundant word line block includes a number of redundant word lines(RWL) to replace a defective normal word line connected to the defective memory cell. And a decoder selects one normal word line among the normal word lines according to an address signal, and selects the defective normal word line and a redundant word line at the same time when the defective normal word line is selected.