Magnetic field sensor circuit
US7818890B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 20, 2007 |
| Grant date | Oct 26, 2010 |
| Priority date | — |
| Expiry date | Nov 20, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/096
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A magnetic field sensor circuit comprises a first magneto-resistive sensor (Rx) which senses a first magnetic field component in a first direction to supply a first sense signal (Vx). A first flipping coil (FC1) applies a first flipping magnetic field with a periodically changing polarity to the first magneto-resistive sensor (Rx) to cause the first sense signal (Vx) to have alternating different levels synchronized with the first flipping magnetic field. A second magneto -resistive sensor (Ry) senses a second magnetic field component in a second direction different than the first direction to supply a second sense signal (Vy). A second flipping coil (FC2) applies a second flipping magnetic field with a periodically changing polarity to the second magneto -resistive sensor (Ry) to cause the second sense signal (Vy) to have an alternating different levels synchronized with the second flipping magnetic field. The first flipping magnetic field and the second flipping magnetic field have a phase shift. A differential amplifier (AMP1) receives the first sense signal (Vx) and the second sense signal (Vy) to obtain a difference signal (Vd). A first synchronous demodulator (DEM1) receives …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.