Design Considerations for MHz PCB Winding Magnetic Components

High frequency PCB windings magnetic is one of the key components in high power density and high efficiency MHz power converter. High frequency PCB windings magnetic losses are the main limitation for the whole converter efficiency and power density, while the PCB windings losses are the main part of the magnetic losses. Currently, the Dowell’s model is used for the layout of PCB windings. However, the Dowell’s model has its restrictions, namely, magnetic field is assumed to be distributed evenly in one direction. But the magnetic field around the windings are three-dimensional and unevenly. Therefore, further arrangement of PCB windings is proposed to minimize the PCB windings losses. Besides, the magnetic circuit is analogous to electrical circuit, and the magnetic core structure shape the footprint of the PCB winding, so different magnetic core structure can be proposed for the trade-off design among the high power density, high efficiency, and low temperature stress. Therefore, both PCB winding layout and magnetic core structure design are important for the optimization of high frequency magnetic components.