Hall sensor with high pass hall voltage filter
US4982155A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 29, 1989 |
| Grant date | Jan 1, 1991 |
| Priority date | — |
| Expiry date | Jun 29, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R33/07
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A Hall sensor has at least one Hall element connected to the input of a differential high pass filter which includes a series branch circuit made up of two outer resistors and a central capacitor connected between the two resistors, a first summing circuit with inputs connected across the capacitor plus one of the branch resistors, a second summing circuit connected across the capacitor plus the other of the branch resistors, and a subtraction circuit having the input connected to the outputs of said first and second summing circuits. The subtraction circuit may be a differential amplifier or a differential comparator such as a differential Schmitt trigger circuit. This sensor is particularly advantageous in an electrically noisy environment, for example in use as a combustion-engine-vehicle gear tooth counting sensor, where the high common mode rejection feature of this Hall sensor reduces the chances for false counting.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.