Abstract: A voltage stabilizing circuit is provided between an insulated converter and a non-insulated converter. When an input voltage Vin from the insulated converter rises, a base current Ib is caused to flow into a transistor via a capacitor, thereby causing a collector current Ic that is hfe times larger than the base current Ib to flow into a collector of the transistor. As a result, a capacitance C of the capacitor is caused to produce approximately the same effect as that produced in a case where a capacitor whose capacitance is equivalent to a value obtained by multiplying the capacitance by the current amplification factor hfe of the transistor is inserted between a power supply line and a ground.