Magnetic field sensing device
US7977941B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 25, 2009 |
| Grant date | Jul 12, 2011 |
| Priority date | — |
| Expiry date | Oct 23, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/098
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A magnetic field sensing device for determining the strength of a magnetic field, includes four magnetic tunnel junction elements or element arrays (100) configured as a bridge (200). A current source is coupled to a current line (116) disposed near each of the four magnetic tunnel junction elements (100) for selectively supplying temporally spaced first and second currents. Sampling circuitry (412, 414) coupled to the current source samples the bridge output during the first and second currents and determines the value of the magnetic field from the difference of the first and second values. A method for sensing the magnetic field includes supplying a first current to the current line (116), supplying a second current the current line (116), sampling the value at the output for each of the first and second currents, determining the difference between the sampled values during each of the first and second currents, and determining a measured magnetic field based on the determined difference.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.