Current detector having magnetic core for concentrating a magnetic flux near a hall-effect sensor, and power switch apparatus incorporating same

摘要

A current detector includes a Hall-effect device 18 for detecting a magnetic field generated by a current flowing across a conducting portion; a magnetic core 19 having a first end face for concentrating a magnetic flux and a second end face having a smaller area than the first end face, only the second end face being disposed at a position in close proximity to or in abutment against a magnetic field detecting surface of the Hall-effect device; and a signal processing circuit 26 for processing an output signal from the Hall-effect sensor 18 into a signal representing the current flowing across the conducting portion.