Magnetic field detection apparatus for detecting an external magnetic field applied to a magnetoresistance effect element, and method of adjusting the same

摘要

A magnetic field detection apparatus capable of changing the detection range and detection sensitivity as desired for a specific application is disclosed. A magnetoresistance effect element is applied a bias magnetic field and an external magnetic field. The bias magnetic field and the external magnetic field are generated on the same straight line, and therefore the bias magnetic field functions to hamper the external magnetic field applied to the magnetoresistance effect element. Thus, the magnetization of the free layer of the magnetoresistance effect element is suppressed, and the rotational angle of the magnetized vector is reduced. As a result, the characteristic of the resistance value of the magnetoresistance effect element to the external magnetic field is shifted by an amount equivalent to the bias magnetic field.