Semiconductor memory device capable of reading data of signature fuse through normal read operation and method of reading data of signature fuse in semiconductor memory device through normal read operation

Abstract

In a semiconductor memory device capable of reading data regarding signature fuses through a normal read operation and a method of reading data regarding signature fuses in a semiconductor memory device through the normal read operation, a semiconductor memory device includes a memory cell array with a plurality of memory cells, an input buffer, and an output buffer. The input buffer writes signature fuse data related to signature fuses to the memory cells respectively when the semiconductor memory device enters a test mode. The output buffer reads the signature fuse data from the memory cells during a normal read operation of the semiconductor memory device. The signature fuse data comprises binary data that is determined based on whether the respective signature fuses are cut. Accordingly, the semiconductor memory device does not require connection of the output buffer to test-related circuits for outputting the signature fuse data while operating in a test mode. As a result, loads on the output buffer do not increase, and therefore, the speed of reading data from the output buffer is not adversely impacted during a normal read operation.