Digital magnetic current sensor and logic
US7635993B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 11, 2005 |
| Grant date | Dec 22, 2009 |
| Priority date | — |
| Expiry date | Nov 14, 2026 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49002
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A sensor for sensing magnetic field strength has a sensor element, and detection circuitry for detecting a level of resistance of the sensor element, the level of resistance varying with magnetic field under test and having hysteresis, so that upon electromagnetic excitation the resistance can switch between two or more stable levels as the magnetic field under test varies. The sensor outputs a digital signal according to the level of resistance. The sensor output may further be interpreted in terms of a change-of-state upon electromagnetic excitation. As the sensor no longer needs a different characteristic from magnetic memory cells, it can be much easier to construct and to integrate with magnetic memory cells than an analog sensor. An excitation signal varies a threshold for the magnetic field under test at which the resistance switches, to enable multiple measurements with different thresholds. Multiple sensor elements can have different thresholds, by having differing geometry or size. It has applications in current sensing, and programmable magnetic logic, when multiple input currents are sensed. Changing the threshold can change the logic operation between AND and OR.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.