Abstract: Systems, methods, and apparatus for differential magnetic field torque sensors that include first and second magnetic targets for coupling to one or more rotatable shafts. The magnetic targets can include multipole ring magnets having a plurality of alternating magnetic domains. First and second differential magnetic field angular position sensors positioned proximate to the magnetic targets produce angular position of the targets and a processing unit is operative to receive an angular position from each of the first and second differential magnetic field angular position sensors and determine a difference between the angular positions. The difference corresponds to an angle between the targets, and the processing unit is operative to calculate, based on the angle, a torque applied to the one or more rotatable shafts.

Abstract: Methods and apparatus for a magnetic field sensor having first and second arrays of magnetic field sensing elements with at least first and second orthogonal axes of sensitivity. The first array of magnetic field sensing elements is spaced a first distance from the second array of magnetic field sensing elements. A turns counter counts a number of times a magnetic pole pair of a moving target passes the magnetic field sensing elements with a selected pole pair resolution and a module determines absolute angular position of the target from differential signals from the first and second arrays of magnetic field sensing elements and the turns counter. The first distance is configured to match a pitch of the poles of the target.

Abstract: In one aspect, an angle sensor includes a first Hall element disposed on a first axis, a second Hall element disposed on a second axis perpendicular to the first axis and a conduction path having a first portion extending parallel to the first axis and a second portion parallel to the second axis. The conduction path is configured to conduct a calibration current that generates a first magnetic flux density measured at the first Hall element and a second magnetic flux density measured at the second Hall element. The angle sensor also includes calibration circuitry configured to generate one or more compensation signals based on the first and second magnetic flux densities and to adjust an external magnetic flux density measured at the second Hall element due to an external magnetic field using the one or more compensation signals to reduce angle error of the angle sensor.

Abstract: In one aspect, an angle sensor includes a first Hall element disposed on a first axis, a second Hall element disposed on a second axis perpendicular to the first axis and a conduction path having a first portion extending parallel to the first axis and a second portion parallel to the second axis. The conduction path is configured to conduct a calibration current that generates a first magnetic flux density measured at the first Hall element and a second magnetic flux density measured at the second Hall element. The angle sensor also includes calibration circuitry configured to generate one or more compensation signals based on the first and second magnetic flux densities and to adjust an external magnetic flux density measured at the second Hall element due to an external magnetic field using the one or more compensation signals to reduce angle error of the angle sensor.