Planar integrated magnetic component with transformer and inductor using multilayer printed wiring board

A new planar integrated magnetic component using multilayer printed wiring board (ML-PWB) technology has been developed for use in switching power supplies. This component integrates a transformer and a choke coil. The transformer is located in the outer ring, and the choke coil is in the inner ring. We designed this component to reduce the loss and the height, especially focusing on the relationship of winding resistance to the thickness of copper foil. This integrated magnetic component was utilized in switching power supplies to evaluate the properties. The experimental results show that the component offers better efficiency and lower electromagnetic noise than conventional components.