Interference-insensitive determination of a capacitance

A measuring arrangement for determining a capacitance of a capacitive element, the measuring arrangement comprising:

• a connection to connect the capacitive element to the measuring arrangement;
• a circuit that is configured, during each measurement cycle of a plurality of successive measurement cycles,
• to connect the capacitive element to a voltage source in order to charge the capacitive element;
• and
• to subsequently transfer an amount of charge from the capacitive element to a further capacitive element of the measuring arrangement;
• and
• a computing unit that is configured, following the plurality of measurement cycles, to determine a measured value with an Analog to Digital Converter (ADC) relating to a total amount of charge transferred as a whole to the further capacitive element during the plurality of measurement cycles and to determine the capacitance of the capacitive element depending on the measured value,
• wherein the computing unit is configured to:
• define a first period for a first subset of the plurality of measurement cycles;
• and
• define a second period for a second subset of the plurality of measurement cycles;
• wherein:
• each of the measurement cycles contains a charging section, where the capacitive element is charged by the voltage source during the charging section, and
• each of the measurement cycles contains a transfer section, where the amount of charge is transferred from the capacitive element to the further capacitive element during the transfer section;
• each of the measurement cycles contains an intermediate section between the charging section and the transfer section, where the capacitive element is neither charged nor discharged during the intermediate section;
• a first intermediate duration is defined for the respective intermediate section of the measurement cycles of the first subset in order to define the first period and a second intermediate duration is defined for the respective intermediate section of the measurement cycles of the second subset in order to define the second period, and
• the second intermediate duration differs from the first intermediate duration.