Operator device and method for operating a capacitive sensor

A capacitive sensor, comprising:

• an operator device, including:
• a voltage application device configured to selectively apply:
• (i) at least a first constant voltage unequal to zero between a seismic mass of the capacitive sensor and at least one electrode of the capacitive sensor, and (ii) a second constant voltage unequal to zero between the seismic mass of the capacitive sensor and the at least one electrode of the capacitive sensor, and
• an electronic device configured to determine an actual gap distance between the seismic mass and the at least one electrode and/or an actual variable for a sensitivity of the capacitive sensor, taking into account:
• (i) at least the first constant voltage, a first natural frequency, self-determined by the electronic device or provided to the electronic device, of a first harmonic vibration of the seismic mass along a spatial direction, centrally intersecting the seismic mass and the at least one electrode, when the first constant voltage is applied between the seismic mass and the at least one electrode, and (ii) the second constant voltage and a self-determined or provided second natural frequency of a second harmonic vibration of the seismic mass along the spatial direction, centrally intersecting the seismic mass and the at least one electrode, when the second constant voltage is applied between the seismic mass and the at least one electrode.

A method for operating a capacitive sensor, comprising the following steps:

• applying a first constant voltage unequal to zero between a seismic mass of the capacitive sensor and at least one electrode of the capacitive sensor, and applying a second constant voltage unequal to zero between the seismic mass and the at least one electrode;
• determining a first natural frequency of a first harmonic vibration of the seismic mass along a spatial direction, centrally intersecting the seismic mass and the at least one electrode, when the first constant voltage is applied between the seismic mass and the at least one electrode, and determining a second natural frequency of a second harmonic vibration of the seismic mass along the spatial direction, centrally intersecting the seismic mass and the at least one electrode, when the second constant voltage is applied between the seismic mass and the at least one electrode;
• and
• determining an actual gap distance between the seismic mass and the at least one electrode and/or an actual variable for a sensitivity of the capacitive sensor, taking into account at least the first constant voltage, the determined first natural frequency, the second constant voltage, and the determined second natural frequency.