Magnetic balance type current sensor
US8754642B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 18, 2011 |
| Grant date | Jun 17, 2014 |
| Priority date | — |
| Expiry date | Apr 15, 2032 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/006
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A magnetic balance type current sensor includes a magnetoresistance effect element whose resistance value changes owing to the application of an induction magnetic field from a current to be measured; a feedback coil disposed in the vicinity of the magnetoresistance effect element and generating a cancelling magnetic field cancelling out the induction magnetic field; a magnetic field detection bridge circuit including two outputs causing a voltage difference corresponding to the induction magnetic field to occur; and a magnetic shield attenuating the induction magnetic field and enhancing the cancelling magnetic field, wherein, on the basis of the current flowing through the feedback coil at the time of an equilibrium state in which the induction magnetic field and the cancelling magnetic field are cancelled out, the current to be measured is measured, wherein the feedback coil, the magnetic shield, and the magnetic field detection bridge circuit are formed on a same substrate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.