Offset suppression in micromachined Lorentz force magnetic sensor by current chopping
US9891290B2 · kind B2 · utility
1Cited by
2References
20Claims
0Family size
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Key dates
| Filing date | Jun 2, 2016 |
| Grant date | Feb 13, 2018 |
| Priority date | — |
| Expiry date | Jun 22, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/0385
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Offsets (short and long term) are significantly reduced in a Lorentz force magnetometer circuit. A modulated bias current supplied to the magnetometer is chopped by periodically switching its polarity. Magnetometer output is demodulated, then de-chopping performed to restore signal polarity output. Chopping of the bias current signal polarity modulates magnetic field signal to a frequency in which electrostatic force remains constant toward eliminating offset and long-term drift from said micromechanical resonator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.