Trade-Off Design of AC Resistance and Parasitic Capacitance in Planar Transformer

To overcome the limitations of copper thickness and parasitic capacitance in planar transformer, this paper proposes the trade-off design of parallel windings based on analytical models of AC resistance and CM parasitic capacitance. With the proposed winding arrangement, the planar transformer can have both low AC resistance and low CM parasitic capacitance, which will lead to lower winding losses and better EMI performance. Proposed trade-off design is verified by FEM simulations and experiments.