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

Hans-Peter Hohe

Michael Hackner

Markus Stahl-Offergeld

Josef Sauerer

Roland Ernst

Norbert Weber

Markus Sand

Dieter Seitzer

Volker Peters

Bernd Dorsch

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

A device for detecting a position of a position indicator includes an electrical magnetic field source, a sensor and an evaluator. The electrical magnetic field source is configured to generate a magnetic field when an electrical current flows through the electrical magnetic field source. The sensor is configured to detect the magnetic field and provide sensor signals based on the magnetic field detected, the sensor having at least two sensors each of which is configured to detect a spatial direction component of the magnetic field and output a signal corresponding to the spatial direction component. The evaluator is configured to receive the sensor signals and determine the position of a position indicator based on the sensor signals when the magnetic field in the surroundings of the electrical magnetic field source is influenced by the position indicator.

Device and method for detecting a position of a position indicator

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.

Electrical circuit

Magnetic field sensor having a vertical Hall sensor element arranged in a semiconductor substrate, and an exciting conductor arrangement having at least one exciting conductor, the exciting conductor being arranged within an exciting conductor plane which is spaced apart, in parallel to the substrate surface, from the vertical Hall sensor element at a vertical distance hhaving a tolerance range &#x394;hwhich is due to the manufacturing process, and which exciting conductor further has a lateral distance das an offset from a center position which is located, in relation to the substrate surface, perpendicularly to the vertical Hall sensor element, and the lateral distance dbeing dimensioned such that a vertical calibration component Bof a magnetic flux density Bcreated by the exciting conductor arrangement in the vertical Hall sensor element changes by less than 5% within the tolerance range &#x394;hfor the vertical distance h.

Calibratable magnetic field sensor and method of producing same

A sensor assembly for determining a magnetization direction of an indicator magnet with respect to the sensor assembly includes a first magnetic field sensor for detecting a first and a second magnetic field component with respect to a first and a second spatial direction, and a second magnetic field sensor for detecting a third and a fourth magnetic field component with respect to the second spatial direction, wherein the first and the second magnetic field sensor are spaced apart from one another. Further, the sensor assembly includes a processor that is implemented to combine the first and the second magnetic field component to obtain a first combination quantity, to combine the third and the fourth magnetic field component to obtain a second combination quantity, to determine a position of the indicator magnet and the magnetization direction.

Sensor assembly and method for determining a magnetization direction of an indicator magnet

A magnetic field sensor for detecting first, second, and third spatial components of a magnetic field at a reference point includes a first sensor element arrangement for detecting the first magnetic field component having a first measurement field component and a first calibration field component with respect to a first spatial axis at a reference point, a second sensor element arrangement for detecting the second magnetic field component having a second measurement field component and a second calibration field component with respect to a second spatial axis y at the reference point and a third sensor element arrangement for detecting the third magnetic field component having a third measurement field component and a third calibration field component with respect to a third spatial axis x at the reference point. An excitation line is arranged such with respect to the three sensor element arrangements that when impressing a predetermined current into the excitation line respective predetermined calibration field components with respect to the spatial axes in the sensor element arrangements are generated.

Magnetic field sensor calibratable during measurement operation and method for calibrating a magnetic field sensor during measurement operation

In determining an exciter conductor spacing of an exciter conductor of an exciter conductor structure from a sensor element of a calibratable magnetic field sensor, first and second electric currents are impressed into the first and second exciter conductors of the exciter conductor structure to generate first and second magnetic field components in the sensor element of the magnetic field sensor, and a quantity is determined depending on the first and second magnetic field components by means of the sensor element. Further, the exciter conductor spacing of the exciter conductor from the sensor element of the magnetic field sensor is established in dependence on an exciter conductor intermediate spacing between the first exciter conductor and the spaced-apart second exciter conductor and the quantities depending on the first and second magnetic field components.

Method for determining an exciter conductor spacing from a magnetic field sensor, method for calibrating the magnetic field sensor as well as calibratable magnetic field sensor and usage of an exciter conductor structure for determining an exciter conductor spacing

An embodiment of a method for a determination, section after section, of a parameter-dependent correction value approximation course includes determining a first measurement signal value with a first parameter value associated with a sensor arrangement when the first parameter value fullfils a predetermined condition or a trigger condition is fulfilled, changing the first parameter value to obtain a second parameter value, determining a second signal value with the second parameter value and determining a second partial section of the correction value approximation course for a second parameter range based on a functional connection describing the second partial section, the first parameter value, the second parameter value, the first measurement signal value, the second measurement signal value and an initial correction value.

Method for determining, section after section, a parameter-dependent correction value approximation course and sensor arrangement

A calibratable magnetic field sensor for sensing a first and a second spatial component of a magnetic field in a reference point, wherein the magnetic field includes a first and a second measurement field component and/or a first and a second calibration field component. The magnetic filed sensor includes a first sensor element arrangement including at least a first and a second sensor element for sensing the first magnetic field component, which includes a first measurement field component and/or a first calibration field component, with respect to a first spatial axis in the reference point. Furthermore, the magnetic field sensor includes a second sensor element arrangement for sensing the second magnetic field component, which includes a second measurement field component and/or a second calibration field component, with respect to a second spatial axis in the reference point. The magnetic filed sensor also includes an excitation line arranged with respect to the first sensor element arrangement so that, when impressing a default current into the excitation line, a pair of different asymmetrical default calibration field components in the first sensor element and in the second sensor element is generated with respect to the first spatial axis in the first sensor element arrangement, wherein the two spatial axes pass along linearly independent position vectors.

Calibratable multidimensional magnetic point sensor

In a method and a sensor arrangement for processing sensor signals of a sensor, which is operated in a plurality of measurement cycles with successive phases with different driving, before the amplification, the sensor signals of n phases of each measurement cycle are weighted with negative mathematical sign and the sensor signals of the remaining n phases of the measurement cycle are weighted with positive mathematical sign by a modulation. Before the amplification, an offset averaged from the sensor signals of the two phases is subtracted from the sensor signals of each two of the phases which were weighted with different mathematical sign and have an offset of the same mathematical sign after the modulation. The artificially generated offset is eliminated again by a demodulation after the amplifier and a summation over the digitized signals of each measurement cycle.

Method for processing sensor signals subject to an offset and sensor arrangement designed to carry out the method

A switching regulator for generating a regulated output voltage comprises a charging switch, a network with a coil, a capacitor and a diode as well as a control to open and close the charging switch. On the output side, the network has a positive output rail and a negative output rail, wherein the output voltage to be regulated is applied between the positive output rail and the negative output rail. The control is formed to control a change-over switch to connect the control input of the charging switch either to the positive output rail or the negative output rail via a potential coupling means. Thus, for controlling the switch, no individual potential has to be generated, but the potential at the positive output rail or the negative output rail, which is anyway applied, is used for controlling the charging switch. Thereby, the inventive switching regulator can be structured in a simple way and, additionally, provides defined and fast startup without requiring additional startup circuits.

Switching regulator

A control device for controlling a charging switch in a switching regulator with an inductance, a filter capacitance and a diode comprises a clock generator for providing an operating clock, an output voltage detection means and an inductance current detection means, as well as a comparator for comparing the detection signals generated by the two detection means. The charging switch is switched on by an event in the clock and switched off when the comparator determines a predetermined relation between the two detection signals. The voltage detection signal is formed to have an inverted curve in relation to the detected output voltage, such that when the output voltage to be detected increases the detection signal falls and vice versa. Thus, a stable and simple regulation of the output voltage across a current locked loop is possible, where no filtering of an actual value has to be performed. Thus, a stable current locked loop with simple structure is obtained in a wide range.

Control device for controlling a charging switch in a switching regulator and method for controlling a charging switch

A Hall sensor array for offset-compensated magnetic field measurement comprises a first and at least one additional pair of Hall sensor elements. Each Hall sensor element has four terminals, of which two act as power supply terminals for supplying an operating current and two act as measurement terminals for measuring a Hall voltage. Respective first supply terminals of each Hall sensor element are connected together and to a first terminal of a common voltage source and respective second supply terminals of each Hall sensor element are connected together and to a second terminal of the common voltage source so that the common voltage source supplies an operating current for the Hall sensor elements. The Hall sensor elements are operated in the spinning current mode so that the offset voltages of the Hall sensor elements approximately cancel one another out in a revolution so that the Hall signal contributions which actually depend on the magnetic field remain.

Hall sensor array for measuring a magnetic field with offset compensation

A Hall element comprises a region having a non-zero Hall constant, a first contact for supplying an operating current to the region, a third contact for conducting the operating current from the region, the first and third contacts defining a direction of the operating current within the region, a second and a fourth contact for tapping a Hall voltage, and a conductor pattern connected to the first contact or to the third contact and substantially surrounding the region laterally or being arranged above or below the region. The conductor pattern has the effect that the intrinsic field of the operating current through the Hall element is suppressed outside the Hall element such that the Hall element effects an at least reduced offset in adjacent Hall elements. In addition thereto, the arrangement of the conductor pattern has the effect that effects of the current return on the Hall voltage generated by the Hall element itself are also at least reduced. An offset reduction is possible simultaneously on an element, by way of suitable implementation, also for both operating current directions in a spinning-current operating mode.

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Heiligenstadt, Germany

Hans-Peter Hohe