Sensor Arrangement and Method for Operating a Sensor Arrangement

• Main Authors: OBERHOFFNER GERHARD, RIEDMUELLER KURT, FORSYTH RICHARD, MASCHERA DAVIDE
• Format: Patent
• Language: English
• Published: 09.06.2011
• Subjects: ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVEREDIN A SINGLE OTHER SUBCLASS; MEASURING; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS; MEASURING LENGTH, THICKNESS OR SIMILAR LINEARDIMENSIONS; MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR; PHYSICS; TARIFF METERING APPARATUS; TESTING

A sensor arrangement has a plurality of Hall sensor devices, each configured to provide a sensor voltage in response to a magnetic field intensity. A selection unit is configured to forward either of the sensor voltages in response to a selection signal. A transconductance amplifier is configured to generate a sensing current depending on a forwarded sensor voltage. A filter stage has a resistor and a filter capacitor connected in parallel in a switchable manner in response to a first switching signal. The filter stage is configured to generate a filtered voltage across the filter capacitor depending on a sensing current. A capacitive analog-to-digital converter has an input capacitor being connected to the filter capacitor in a switchable manner in response to a second switching signal. The analog-to-digital converter is configured to generate a digital sensor value based on a filtered voltage. The sensor arrangement further has a control circuit which is configured to generate the selection signal and the first and the second switching signals such that for each of the forwarded sensor voltages in a first time segment, the filtered voltage across the filter capacitor is generated, and in a second time segment, the input capacitor is connected to the filter capacitor.