Displacement sensor using gmr elements, angle sensor using gmr elements, and semiconductor device used for them

摘要

A highly accurate displacement sensor using GMR elements (2) for detecting a displacement of a physical quantity such as angle is to be provided wherein a waveform distortion of output voltage is diminished.

<Paragraphs id="pa02" num="0002" xmlns:base="http://www.sipo.gov.cn/XMLSchema/base">There are installed at least two Wheatstone bridge circuits having a predetermined angular offset and each comprising a plurality of GMR elements (2a-2h), the GMR elements (2a-2h) each having a fixed magnetic layer (19) set to a predetermined magnetization direction (13). An AC power supply is use as a power supply of the Wheatstone bridge circuits and a displacement of a physical quantity such as a rotational angle is detected on the basis of AC-modulated outputs from the Wheatstone bridge circuits.

<Paragraphs id="pa03" num="0003" xmlns:base="http://www.sipo.gov.cn/XMLSchema/base">An anisotropic self-bias effect of a free magnetic layer (21) in each GMR element can be diminished and hence it is possible to remedy a waveform distortion of an output signal based on the anisotropic self-bias effect of the free magnetic layer (21).