US Patent 7447090 Semiconductor memory device

A semiconductor memory device includes: a first bit line sense amplifier array for amplifying a data input to a first bit line pair coupled to cells; a second bit line sense amplifier array for amplifying a data input to a second bit line pair coupled to the cells; and a control unit for activating one of the first and second bit line sense amplifier arrays and, after a predetermined time, for activating the other bit line sense amplifier array in response to an active signal and a column address information signal.