Bipolar chopping for 1/f noise and offset reduction in magnetic field sensors
US10281531B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 4, 2016 |
| Grant date | May 7, 2019 |
| Priority date | — |
| Expiry date | Jul 28, 2037 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/098
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A chopping technique, and associated structure, is implemented to cancel the magnetic 1/f noise contribution in a Tunneling Magnetoresistance (TMR) field sensor. The TMR field sensor includes a first bridge circuit including multiple TMR elements to sense a magnetic field and a second circuit to apply a bipolar current pulse adjacent to each TMR element. The current lines are serially or sequentially connected to a current source to receive the bipolar current pulse. The field sensor has an output comprising a high output and a low output in response to the bipolar pulse. This asymmetric response allows a chopping technique for 1/f noise reduction in the field sensor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.