SEMICONDUCTOR STORAGE DEVICE

摘要

PROBLEM TO BE SOLVED: To efficiently execute the operation test of an input/output circuit of a semiconductor memory device operating at a data input/output frequency higher than an internal operation frequency. SOLUTION: The input/output circuit 110 has an S/P data conversion circuit 130 which subjects the serial data inputted to a data terminal to serial-parallel conversion and transmits the data to write data lines WDA to WDd, a P/S data conversion circuit 140 which subjects the parallel data of read data line RDA to RDd to parallel-serial conversion and outputs the serial data to the data terminal and an input/output test circuit 150 which is arranged between the write data lines WDA to WDd and the read data line RDA to RDd. The input/output test circuit 150 transmits the data of the write data lines WDA to WDd directly to the read data line RDA to RDd without through memory cell arrays in response to an input/output circuit test signal TST.