Magnetic device and frequency analyzer
US7808229B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 10, 2007 |
| Grant date | Oct 5, 2010 |
| Priority date | — |
| Expiry date | Dec 15, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10N50/10
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A magnetic device and a frequency analyzer are provided as those industrially utilizing a resonance phenomenon of a direction of magnetization of a magnetoresistive element. Since polarities of an alternating current i vary with time, the direction of magnetization oscillates as affected by the magnitude and frequency of the alternating current. When the frequency fF of the direction of magnetization of a free layer in the magnetoresistive element coincides with the frequency f of the alternating current flowing in the magnetoresistive element, the oscillation of the direction of magnetization resonates to increase a voltage between output terminals. A magnetic yoke applies such a magnetic field as to cause resonance, to the free layer. A direct current is used as an electric current outputted from a current control circuit and, while this direct current is swept, voltages at respective specific resonance frequencies are detected by a monitor circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.