Semiconductor memory device with switching element for isolating bit lines during testing

摘要

A semiconductor recording device includes two transistors connected to two bit lines, respectively, that are turned OFF by a retention test signal during a retention test. One of the bit lines is put into high impedance with the help of a write driver, and "0" is output to the other bit line. Therefore, charge at H-level is not supplied to the bit lines during the retention test, so that a memory cell having a faulty connection will not temporarily retain H-level data.