Patent ID: 9575143
Date: 2017-02-21
CPC Classifications: G01R

Claim:
1. A single-chip two-axis magnetic field sensor, comprising: a semiconductor substrate; two mutually orthogonal sensing axes, the X-axis and the Y-axis; a referenced bridge sensor integrated on the semiconductor substrate, the referenced bridge sensor having a sensitive direction along the Y-axis, wherein the referenced bridge comprises reference elements and sense elements, wherein the sense elements have a magnetoresistive transfer curve strongly dependent on applied magnetic fields and the reference elements have a magnetoresistive transfer curve weakly dependent on an applied magnetic field; a push-pull bridge sensor integrated on the semiconductor substrate, the push-pull bridge sensor having a sensitive direction along the X-axis, wherein the push-pull bridge is comprised only of sense elements; and each of the reference elements and each of the sense elements including a magnetic sensor element, the magnetic sensor element being either a tunneling magnetoresistance (TMR) element or a giant magnetoresistance (GMR) element, wherein the magnetic sensor elements in the referenced bridge sensor and the magnetic sensor elements in the push-pull bridge sensor have a common pinning direction, and wherein a technique is implemented to reduce sensitivity of the reference elements to applied magnetic fields such that the reference elements have the magnetoresistive transfer curve weakly dependent on the applied magnetic field, the technique being selected from the group of techniques consisting of: shielding, shape anistropy stabilization, exchange bias, and magnetic field bias.