Inductor using multilayered printed circuit board for windings

Abstract

An inductor or transformer uses a multilayer printed circuit board to form the conductor turns. Each layer comprises a dielectric sheet and a conductor printed on the sheet. Each of the conductors has approximately the same shape as each other (such as circular or rectangular), is superimposed on the other conductors and is substantially closed on itself (with a gap to separate the two ends). A multiplicity of through-hole vias are evenly spaced around the conductors and pass through the multiplicity of layers. Successive vias make an electrical connection between successive pairs of adjacent conductors such that current passes in the same direction through all of the conductors. Each layer provides (N-1)/N turns such that N layers provide N-1 complete turns. A ferrite core material passes through a hole in the printed circuit board within the conductors.