US Patent 9948198 Resonant converter and switching power supply device

A resonant inverter includes a first switch element and a second switch element that are alternately turned on and off, a first capacitor and a second capacitor, a first inverter section constituted by the first switch element and the first capacitor, and a second inverter section constituted by the second switch element and the second capacitor. A first coil and the first capacitor constitute a first resonant circuit included in the first inverter section, and the first coil and the second capacitor constitute a second resonant circuit included in the second inverter section, thereby forming a resonant converter.