Abstract: A ferrite substrate, a winding-embedded ferrite resin layer, and an IC-embedded ferrite resin layer are laminated, the ferrite substrate has a ferrite first protruding part that protrudes into the ferrite resin layer from the surface thereof, the winding inside the ferrite resin layer is arranged winding around the first protruding part, and the IC overlaps the first protruding part in the resin layer. According to this configuration, high integration can be achieved, and the IC is arranged at a site where the ferrite first protruding part, the height of which fluctuates little as a result of thermal expansion, overlaps the ferrite resin layer, the thickness of which is thinned by the first protruding part and varies little as a result of thermal expansion, minimizing variations in the gap between the winding and the IC as a result of thermal expansion, and achieving greater stability of electrical characteristics.

Abstract: A ferrite substrate, a winding-embedded ferrite resin layer, and an IC-embedded ferrite resin layer are laminated, the ferrite substrate has a ferrite first protruding part that protrudes into the ferrite resin layer from the surface thereof, the winding inside the ferrite resin layer is arranged winding around the first protruding part, and the IC overlaps the first protruding part in the resin layer. According to this configuration, high integration can be achieved, and the IC is arranged at a site where the ferrite first protruding part, the height of which fluctuates little as a result of thermal expansion, overlaps the ferrite resin layer, the thickness of which is thinned by the first protruding part and varies little as a result of thermal expansion, minimizing variations in the gap between the winding and the IC as a result of thermal expansion, and achieving greater stability of electrical characteristics.