US 9,007,054 B2 · Angle sensor with misalignment detection and correction

Abstract

An angle sensor to provide sensor-to-magnet misalignment detection and correction capability in rotation angle measurement applications is presented. The angle sensor has magnetic field sensing elements to sense magnetic field associated with a rotating magnet. The angle sensor includes circuitry to generate signals based on the sensing by the sensing elements. The signals provide information that can be combined according to an error function to provide misalignment detection. The angle sensor can be used with or can be incorporated in an angle measurement device that employs a processing unit to produce a rotation angle value. In one embodiment, the processing unit is configured to implement the error function and correct the angle value for detected misalignment. In another embodiment, the error function is performed by a programming device and detected misalignment is corrected through mechanical adjustment of sensor-to-magnet position.

Claims16

Dependent claims

An angle measurement device comprising:

an angle sensor comprising:
magnetic field sensing elements including a first sensing element, a second sensing element and a third sensing element located between the first and second sensing elements, to sense magnetic field associated with a rotating magnet, the first and second sensing elements being located so that sensing by the first sensing element is indicative of a sine function and sensing by the second sensing element is indicative of a cosine function when the angle sensor is aligned with the magnet;
circuitry, coupled to the magnetic field sensing elements, to generate first, second and third angle sensor output signals based on the sensing by the first, second and third sensing elements, respectively;
and
a processing unit, coupled to the angle sensor, to produce an output value based on the first, second and third angle sensor output signals and comprising an error determiner configured to generate an error value indicative of misalignment between the angle sensor and the magnet as a combination of the first, second, and third signals.

2 more elements

Dependencies are inferred from the claim text.

Angle sensor with misalignment detection and correction

Life of this patent

Angle sensor with misalignment detection and correction

Life of this patent

Abstract

Claims16