Magnetic field sensor

Abstract

A magnetic field sensor includes a magnetic detection element that includes a magnetic material causing a magnetic impedance effect and a bias coil applying a bias magnetic field to the magnetic material, a high-frequency oscillation circuit that supplies a high-frequency current to the magnetic material, an AC bias circuit that supplies an AC bias current to the bias coil, and a detection circuit that sets a reference point corresponding to an extreme impedance position in a characteristic of the magnetic detection element in the state of no application of an external magnetic field and outputs an electric signal changing in response to an impedance change amount from the reference point. The detection circuit includes an amplitude detection circuit which detects an amplitude of the electric signal at a timing of each vertex in which at least a voltage change direction of the electric signal changes.

Dependencies are inferred from the claim text.