Current transformer using a laminated toroidal core structure and a lead frame

摘要

A current transformer device (10) is formed on a ceramic substrate (12) which is provided with a plurality of planar conductive tracks (16) formed on a surface of the substrate (12) where the conductive tracks (16) extend substantially radially from an imaginary point on the surface of the substrate (12). A structure of permeable material (25) is then tape cast or epitaxially formed by vapor deposition of a thick film of magnetic ceramic over the major portion of each of the conductive tracks (16) to form a permeable toroidal core (22). A lead frame (38) is then placed over the core (22) and a plurality of metal conductors (26) are soldered to each of the respective exposed ends of the metal conductive tracks (16) on the substrate (12). The required electrical elements (54) to complete the current transformer device (10) are mounted to a second side (14b) of the ceramic substrate (12) and electrically connected to the toroidal coil (13) for powering and/or receiving signals therefrom.