A capacitive measuring system includes capacitive sensors and an evaluation circuit having a multiplexer, a synchronous rectifier, a sinusoidal signal generator, and a reference voltage divider. The capacitive sensors are acted on by a mono-frequency voltage signal generated by the sinusoidal signal generator, output signals of the capacitive sensors are transmitted in alternation to the synchronous rectifier via the multiplexer, and signal amplification of output signals of the synchronous rectifier are calibrated as a function of an activatable reference impedance. The synchronous rectifier is formed by a MOS semiconductor switch. A source-drain section of the MOS semiconductor switch forms a shunt that is controlled by the mono-frequency voltage signal. A channel of the multiplexer is provided for transmitting a calibration signal, generated by the reference voltage divider, to the synchronous rectifier alternately with the output signals of the capacitive sensors.


    Access

    Download


    Export, share and cite



    Title :

    Capacitive Measuring System


    Contributors:
    ZELENY TORBEN (author) / BORGMANN UWE (author) / FREIWALD JAN (author)

    Publication date :

    2020-11-19


    Type of media :

    Patent


    Type of material :

    Electronic Resource


    Language :

    English


    Classification :

    IPC:    B60R Fahrzeuge, Fahrzeugausstattung oder Fahrzeugteile, soweit nicht anderweitig vorgesehen , VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR / G01D MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE , Anzeigen oder Aufzeichnen in Verbindung mit Messen allgemein / G01R Messen elektrischer Größen , MEASURING ELECTRIC VARIABLES



    Capacitive measuring system

    ZELENY TORBEN / BORGMANN UWE / FREIWALD JAN | European Patent Office | 2024

    Free access

    Capacitive fluid level measuring

    Embrey,D.M. / AB Electronic Products,GB | Automotive engineering | 1984


    Method for measuring capacitance and capacitive sensor unit

    WEINGAERTNER THOMAS / WUERSTLEIN HOLGER / POHL FLORIAN | European Patent Office | 2016

    Free access


    Capacitive sensing system

    TABACZYNSKI MICHAEL | European Patent Office | 2017

    Free access