Abstract: A boost signal generating circuit providing a higher boosted voltage in a shortened time period but with minimum power consumption. The boost signal generating circuit includes a boosting circuit including first and second MOS transistors, a capacitor and a charging device, a dynamic inverter circuit including third and fourth MOS transistors, a boost potential generator circuit, and a fifth MOS transistor having a source serving as a boost signal source. The fifth MOS transistor is turned on by a charging current supplied by the charging device to thus raise its source potential, while simultaneously the dynamic inverter circuit is actuated to actuate a boostrap circuit, thereby to raise its output voltage and hence reduce the on resistance of the fifth MOS transistor, resulting in a boosted signal at a potential near the output voltage of the boost potential generator circuit.