Fraunhofer-Gesellschaft Zur Foerderung Der Angewandten Forschung E.V.

Markus Sand

Hans-Peter Hohe

Michael Hackner

Markus Stahl-Offergeld

Philip Beran

The present invention relates to a Hall effect sensor which is integrated in a semiconductor substrate and enables measurement of a magnetic field component. perpendicularly to the surface of the semiconductor substrate. The Hall effect sensor comprises several Hall elements having an electrically conductive semiconductor region which has a straight-line row of electrical measuring and control contacts on an end face on the substrate surface. The Hall elements are designed or can be operated in such manner that they have a sensitivity both to a magnetic field component parallel to and the magnetic field component perpendicular to the substrate surface of the semiconductor substrate (). Several of the Hall elements are arranged such that their sensitivity to a magnetic field component parallel to the substrate surface of the semiconductor substrate can be compensated mutually by circuitry or in a signal evaluation. In this way, a sensitivity of these Hall elements to the magnetic field component perpendicular to the substrate surface of the semiconductor substrate is obtained. By using these Hall elements for measuring the magnetic field component perpendicularly to the substrate surface, a very low sensitivity to mechanical stresses can be achieved.

Hall sensor with hall elements measuring magnetic field components perpendicularly to the substrate surface

A central idea of techniques herein is that by means of modulation or variation of the supply signal of a Hall sensor, the useful signal portion in the resulting sensor output signal can be separated from the offset portion during operation of the Hall sensor, with no previous calibration or previous serial tests. That course of the sensor output signal resulting from the modulation or variation of the supply signal can then be evaluated or decomposed relative to the components which can be attributed to the offset portion and the useful signal portion. Thus, the offset portion in the sensor output signal can be determined with no (or a negligibly small) external magnetic field applied or with an external magnetic field applied, in case the external magnetic field is constant within a tolerance range while determining the offset portion.

Method for offset compensation of a sensor signal of a hall sensor and sensor arrangement

The present invention relates to a method and a device for measuring currents or magnetic fields using at least one Hall sensor, which is operated with spinning current technology. In addition to first sample values for calculating a spinning current measurement value (), second sample values are formed from the digitally converted sensor signals () of the Hall sensor in the method. The second sample values are formed over shorter periods of time () and are corrected with an offset, which is calculated from the spinning current measurement value () and the first sample values. In addition to the precise spinning current measurement value (), fast offset-corrected measurement values () of the magnetic field or current are obtained using the method and the associated device, without elaborate calibration or additional analog circuitry expenses.

Method and device for measuring currents or magnetic fields using hall sensors and their offset-corrected measurement values

An electrical circuit includes a signal processing chain and a controller. The signal processing chain includes an integrator configured to integrate an input signal over an integration time. The controller is connected to a signal output of the signal processing chain to receive and evaluate an output signal of the signal processing chain. The controller is further configured to adapt the integration time based on the output signal.

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Taennesberg, Germany

Markus Sand