Abstract: In a method for detecting an offset drift in a resistive Wheatstone measuring bridge, a switch is made between a measuring mode and a testing mode without interfering in the internal structure of the measuring bridge. In testing mode, two sensor resistors that act in the same way and lie in different bridge arms in the measuring mode are connected in series, and a voltage level occurring in the connection of these sensor resistors is compared with a reference voltage. Preferably the sensor resistor that acts in a different way and lies between the two series-connected sensor resistors acting in the same way is bridged. The reference voltage is advantageously formed by resistive division of the voltage applied to the series connection of the sensor resistors. The testing mode may expediently be switched in such a way that the two pairs of sensor resistors acting in the same way are respectively tested in succession.
Type:
Grant
Filed:
February 18, 2005
Date of Patent:
August 8, 2006
Assignees:
Fraunhofer-Gesellschaft zur Forderung der angewandten Forschung e.V., Intelligente Sensorsysteme Dresden GmbH
Inventors:
Peter König, Stefan Krone, Stefan Woschech, Matthias Böhm, Andreas Schroth