Semiconductor memory device having a plurality of blocks each including

Abstract

A semiconductor memory device according to the present invention includes a plurality of blocks. A plurality of first selection signals, second selection signals, and third selection signals are provided to the blocks. Each block includes: a memory cell array; a read/write circuit for simultaneously reading out a plurality of data from the memory cell array and subsequently simultaneously writing a plurality of further data into the memory cell array when the corresponding first selection signal is active; a parallel/serial conversion circuit for outputting the plurality of simultaneously read out data, the outputting being performed data by data in a serial manner along the time axis; a transfer gate for a reading operation controlled by the corresponding second selection signal, the gate outputting the plurality of data from the parallel/serial conversion circuit when the corresponding second selection signal is active; a serial/parallel conversion circuit for receiving the plurality of further data, the further data being sequential, and for outputting the plurality of sequential data to the read/write circuit in a parallel manner along the time axis; and a transfer gate for a writing operation controlled by the corresponding third selection signal, the gate outputting the plurality of sequential data to the serial/parallel conversion circuit when the corresponding third selection signal is active. Only one second selection signal is allowed to be active at a given time, while the other remain non-active. Only one third selection signal is allowed to be active at a given time, while the other remain non-active.