Controlling the timing for the overdrive of the sense amplifiers in response to the conductor length between the sense amplifiers and the power supply voltage supply nodes, and designing a reduction of the power consumption by preventing excessive overdrive of the bit lines. The supply timing for the power supply voltage to each sense amplifier bank is controlled according to the conductor length between the supply nodes CT0, CT1, CT2 for the power supply used for the driving of the sense amplifiers and each sense amplifier bank SB0 to SB16, and since the supply time for the overdrive voltage to the sense amplifier bank SB0 at the near end is set short and the supply time for the overdrive voltage is set successively longer as it goes towards the far end, the sensing delay that originates in the voltage drop that is generated in the conductor between the supply nodes and the sense amplifier banks is compensated for, uniformity of the overdrive for the bit lines at both the far and near ends can be achieved, the excessive overdrive at the sense amplifier bank (memory cell mat) at the near end can be avoided, and by extension, a reduction of the power consumption can be realized.