Over driver control signal generator in semiconductor memory device

An over driver control signal generator in a semiconductor memory device is provided to decrease operation characteristics degradation and failure of the semiconductor memory device by assuring a stable bit line sense amplifier operation regardless of the level of a power supply voltage. An over driver control signal generator in a semiconductor memory device generates a bit line over driver control signal by receiving an over driving signal generated by receiving an active command. The over driver control signal generator comprises a pulse generation unit(610), a power supply voltage level detection unit(620), and a selection unit(630). The pulse generation unit generates a pulse signal with pulse width corresponding to a desired over driving period in response to the over driving signal. The power supply voltage level detection unit detects a power supply voltage level. The selection unit outputs or blocks the pulse signal as the over driver control signal in response to a detection signal outputted from the power supply voltage level detection unit.