Hybrid closed-loop/open-loop magnetic current sensor

Abstract

Hybrid magnetic current sensors and sensing apparatus are presented with closed-loop and open-loop circuitry employs first and second integrated magnetic sensors to sense a magnetic field in a magnetic core structure gap to provide high accuracy current measurement via a closed-loop magnetic circuit with the first sensor in a nominal current range as well as open-loop current measurement using the second sensor in an extended second range to accommodate over-current conditions in a host system as well as to provide redundant current sensing functionality.

What is claimed is: 
     
         1 . A hybrid closed-loop, open-loop magnetic current sensor, comprising:
 a magnetically susceptible core structure with an opening to accommodate an electrical conductor conducting a current to magnetically interact with the core structure;   a compensation coil having at least one winding around a portion of the core structure;   an integrated circuit positioned at least partially within a gap of the core structure and connected to the compensation coil, the integrated circuit comprising means for testing the current flowing in the electrical conductor using a closed-loop magnetic circuit comprising a first sensor formed on or in the integrated circuit within the gap of the core structure, and means for testing the current flowing in the electrical conductor using an open-loop magnetic circuit comprising a second sensor formed on or in the integrated circuit within the gap of the core structure.