Patent ID: 7839255

Claim:
A composite transformer comprising first and second windings which generate magnetic fluxes when excited and which are wound to form a first inductor, a second inductor, and a transformer, the composite transformer further comprising: a transformer core including a core leg around which a portion of the first winding and a portion of the second winding are wound, and a base fixing the core leg thereof; a first inductor core including a core leg around which another portion of the first winding is wound, and a base fixing the core leg thereof; and a second inductor core including a core leg around which another part of the second winding is wound, and a base fixing the core leg thereof, wherein: the first winding and the second winding are wound in such directions that magnetic fluxes generated by the first and second windings are cancelled with each other; and wherein the first winding and the second winding are wound around the core leg of the transformer core so as to be alternately overlapped with each other, and are respectively wound around the core leg of the first inductor core and the core leg of the second inductor so as to be apart from each other to suppress interference of the magnetic fluxes generated by the first and second windings.