A semiconductor device includes a plurality of memory cells connected to a word line, sense amplifiers arranged correspondingly to the memory cells, and a sense-amplifier control circuit that activates the sense amplifiers in response to selection of the word line and temporarily reduces driving performance of the sense amplifiers in response to a request for writing of data to any one of the memory cells. With this configuration, inverted data can be quickly overwritten to the sense amplifier. Furthermore, because a collective control is executed on the sense amplifiers to be activated, instead of individually controlling the sense amplifiers to be activated, the circuit scale of the sense-amplifier control circuit can be reduced.