Abstract: A booster circuit in which a signal to be boosted and a boost capacitor are electrically separated during driving periods and are electrically coupled during boosting periods so that the capacitive load which the signal to be boosted must drive is significantly reduced. The boost capacitor is preferably charged to a predetermined voltage level prior to the boosting periods. The coupling means used is preferably an insulated gate FET transistor the gate voltage of which is controlled to be not lower than a power source voltage level before the boosting periods of time.