Feedback enhanced sensor, alternating magnetic field detector
US5469058A · kind A · utility
Inventor
Key dates
| Filing date | Dec 30, 1992 |
| Grant date | Nov 21, 1995 |
| Priority date | — |
| Expiry date | Dec 30, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/025
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The present invention features an active sensor for detecting a magnetic field. The sensor includes a pickup coil wound on a semi-flexible bobbin, which in turn is mounted on a suitable core assembly. Optionally, the core/coil assembly can then be mounted on a flexible substrate. Thin strips of either standard or amorphous crystalline high-permeability alloy are laminated to form the core. Once the coil has been assembled with the core laminations, output leads from the coil are connected to conductors of a miniature coaxial cable, the sheath of which is grounded to the core laminations. An operational amplifier is connected to the coil assembly. The operational amplifier has a positive feedback path to substantially cancel the combined dissipative loss of resistance and core eddy currents of the coil assembly. The operational amplifier also has a negative feedback path to set the maximum gain of the active sensor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.