Patent attributes
A semiconductor device includes a column decoder that generates a column selecting signal that selects any of a plurality of bit line pairs to which memory cells are connected according to a column address that is input; a bit line selecting switch that connects by the column selecting signal any of a plurality of bit line pairs and a data I/O line pair that outputs data that has been read from a memory cell to the outside; a data amplifier that amplifies a voltage differential of a data I/O line pair and outputs data that has been read to an output buffer; a data I/O line switch that is provided in the data I/O lines; an I/O line precharge circuit that precharges a data I/O line pair that is not on the side of the data amplifier; and an amplifier precharge circuit that precharges a data I/O line pair that is on the side of the data amplifier.