Patent ID: 9541424
Date: 2017-01-10
CPC Classifications: G01B,G01D,G01R

Claim:
1. A magnetic field sensor, comprising: a semiconductor substrate having a first surface in a coordinate plane; a Circular Vertical Hall (CVH) sensing element comprised of a plurality of vertical Hall elements, wherein each one of the plurality of vertical Hall elements is arranged upon a common circular implant region in the first surface of the semiconductor substrate, wherein the plurality of vertical Hall elements is configured to generate a plurality of output signals responsive to a magnetic field having a direction component, wherein the CVH sensing element is configured to generate a CVH output signal comprised of the plurality of output signals, wherein the magnetic field results from a multi-pole magnet disposed proximate to the magnetic field sensor and having a plurality of north poles and a plurality of south poles, each north pole proximate to at least one south pole; an angle sensing circuit coupled to receive the CVH output signal and configured to generate an angle signal representative of an angle of the direction component of the magnetic field as the multi-pole magnet and the CVH sensing element move relative to each other; a pole pair counting module coupled to receive a signal representative of the angle signal and configured to generate a count signal representative of a count of a number of the pole pairs of the multi-pole magnet that move past the CVH sensing element; and an angle interpolation module coupled to receive the angle signal and the count signal, the angle interpolation module configured to generate a reconstructed angle signal representative of an angular position of the multi-pole magnet relative to the CVH sensing element, the reconstructed angle signal generated based upon the count signal and the angle signal, the reconstructed angle signal having a higher resolution than the angle signal.