Power Supply Circuit and Luminaire

Abstract

According to one embodiment, there is provided a power supply circuit including a direct-current voltage source, a bridge circuit, a transformer, and a rectifying and smoothing circuit. The bridge circuit includes at least one switching element and converts a direct-current voltage supplied from the direct-current voltage source into an alternating-current voltage according to ON and OFF of the switching element. The transformer includes a primary winding wire connected to the bridge circuit and a secondary winding wire magnetically coupled to the primary winding wire. The rectifying and smoothing circuit converts the alternating-current voltage output from the secondary winding wire into a direct-current output voltage and supplies the direct-current output voltage to a direct-current load. The bridge circuit includes a capacitor connected between the primary winding wire and a terminal on a low potential side of the direct-current voltage source.

Dependencies are inferred from the claim text.