Method and device for the simultaneous determination of the temperature and resistance change of sensor resistances of a bridge circuit

摘要

In a method and a device for the simultaneous determination of the temperature and resistance change of one or more sensor resistances of a bridge circuit, which in one embodiment is fed by a constant voltage source, an additional resistor is connected in order to form a series circuit comprising a bridge circuit and an additional resistor. Different voltages are measured in the series circuit, of which at least one voltage drops across one of the resistors of the bridge circuit and which are selected such that the voltage across the bridge circuit can be determined from one or more of the different voltages. From the measured voltages, known resistance values of the resistors and known temperature coefficients α, β of the resistors of the bridge circuit, the temperature change ΔT and therefrom the change in resistance dR is calculated or vice versa. The process does not require an additional temperature sensor and enables, among other things. a more precise determination of the measured variable.