Ultra-low-profile tube-type magnetics

摘要

A low-profile transformer or inductor includes a leg of a magnetically permeable core. A tube-type winding arrangement is made by use of a flat, flexible dielectric sheet, on one side of which a broad conductive area is affixed, and on the other side of which a plurality of mutually parallel elongated regions are affixed. The dielectric sheet is rolled into a tube defining a parting line which is perpendicular to the axes of elongation of the conductive strips. The discontinuous elongated strips are formed into a continuous winding by means of stitches. The stitches may be through vias extending through overlapping regions of the tube to interconnect ends of the strip conductors, or may be generated by an HDI conductor overlying the ends of the strip conductors, with through vias making connections to the ends of the strip conductors and to HDI conductors.