Semiconductor memory device and method of testing semiconductor memory device

摘要

A semiconductor memory device may include a memory that stores data, an input/output unit and a loopback circuit. The input/output unit inputs and outputs data of a predetermined number of bits in synchronization with a clock signal. The input/output unit may include, but is not limited to, the same number of data input/output terminals as the predetermined number of bits. The loopback circuit performs loopback operation to read data of the predetermined number of bits out of a first optional area of the memory and to write the data into a second optional area of the memory.