Patent attributes
There is provided a planar transformer having a dual-bobbin structure. The planar transformer includes a core unit including a pair of cores that are electromagnetically coupled to each other, and a bobbin unit including an inner bobbin part and a board part. The inner bobbin part includes a bobbin body having a predetermined volume and having a through hole into which the core is inserted, and a first winding wound around an outer circumferential surface of the bobbin body, and the board part includes at least one board including a board body having a predetermined surface area and having a through hole into which the inner bobbin part and the core are inserted, and a second winding formed on at least one surface of the board body and causing electromagnetic action with the first winding.