DEVICE AND METHOD FOR EVALUATING SIGNALS OF LOAD CELLS WITH STRAIN GAUGES

A device and a method for evaluating signals from load cells with strain gauges (SG), which require electronic signal evaluation with very low offset voltages due to the small output signal. In order to be able to use inexpensive components as well, two different operating points of the SG are set in two consecutive measurements, each being determined by a single voltage reference. The voltage in the zero branch of the bridge circuit of the SG is amplified in a differential amplifier and digitised with an ADC. In this context, the reference for the ADC is derived from the operating point of the SG that is determined by the respective voltage reference. The digitised offset and the initial value of the load cell are calculated from the two measurement values in an arithmetic logic unit.