Patent ID: 7432793
Filing Date: 2008-10-07
Classification: H01F,H03F,H03H,H05K

Abstract:
1. An output filter for an audio amplifier comprising: a printed circuit board having a first aperture, a second aperture, and a third aperture, the first, second, and third apertures extending through the printed circuit board; a first coil winding formed on a layer of the printed circuit board and substantially surrounding the first aperture; a tank circuit comprising an inductor and a capacitor and coupled to a tap on the first coil winding at a point other than at an end of the first coil winding; a second coil winding formed on a layer of the printed circuit board and substantially surrounding the second aperture; and a magnetic core having a first leg passing through the first aperture, a second leg passing through the second aperture, and a third leg free of a coil winding passing through the third aperture, the third leg having a gap.