Power Supply Device and Luminaire

Abstract

According to one embodiment, a power supply device includes a rectifier circuit, a smoothing capacitor, and a normally on type transistor. The rectifier circuit is configured to rectify an alternating current supplied from a voltage source. The smoothing capacitor is charged by an output current output from the rectifier circuit. The normally on type transistor is connected between the rectifier circuit and the smoothing capacitor in series and is configured to limit an output current value of the rectifier circuit during a voltage input from the voltage source to an output current value higher than an output current value of the rectifier circuit during a steady operation.

Dependencies are inferred from the claim text.