PURPOSE: To secure the effective operation in a starting phase by providing a control unit which opens a first switch and closes a second switch at the time when the voltage of the output terminal of an adjuster reaches a prescribed threshold securing the effective operation of an integrated circuit.

CONSTITUTION: A solid-state switch 11 having a control electrode, an electronic element 12 consisting of a diode or another solid-state switch having a control electrode, and a control unit s to which a voltage is supplied through a conductor 1 and which controls the output voltage through a conductor 6 are provided. The control unit S closes the switch 11 at the time of turning on the adjuster and keeps it closed till arrival of the voltage at the prescribed threshold securing the effective operation of an integrated circuit CI and opens it at the time of this arrival. If the electronic element 12 consists of the switch having the control electrode, the control unit S closes this switch also simultaneously. Thus, the effective operation is always secuted even in the initial starting phase.