Orthogonal winding structures and design for planar integrated magnetics

This paper presents a new winding implementation method for planar integrated magnetics as a means to achieve high efficiency and high power density. The proposed design uses transformer and inductor windings that are orthogonal to each other in their physical orientations to minimize the capacitive coupling between them, as well as to reduce the thickness and the number of layers of the printed circuit board that hosts the windings. The orthogonal winding structures also result in lower dc resistance and significantly less eddy current losses for the vertical inductor windings. Application of the proposed concept is demonstrated by design for a half-bridge dc-dc converter with integrated current doubler rectifier. Finite element analysis and prototype experimental results are presented to validate the proposed concept and its benefits.