A test device includes a data driver and a controller. The controller is configured to generate a test code by dividing a test sequence in a unit of n-bits. The data driver is configured to receive the generated test code and output one of input voltages to a device under test as a test signal based on the generated test code. A storage device stores a test sequence.

The present disclosure relates to a method for determining the conductivity of a medium by means of a conductive conductivity sensor, comprising the steps of determining measured values of the conductivity sensor, determining reference measured values of a reference circuit integrated into the conductivity sensor, deriving at least one adjustment value from the reference measured values of the reference circuit, and correcting the measured values of the conductivity sensor by means of the at least one adjustment value.

Methods and apparatus are provided for detecting sensor wiring faults. A difference is determined between a high voltage and a low voltage. The high voltage and the low voltage are both related to a sensor that includes a high-voltage wire and a low-voltage wire. A determination is made whether the difference has dropped based on a low-voltage threshold. After determining that the difference has dropped, a fault in the high-voltage wire is indicated. A determination is made whether the difference has risen based on a high-voltage threshold, where the low-voltage threshold is less than the high-voltage threshold. After determining that the difference has risen, a fault in the low-voltage wire is indicated.

A method includes setting first and second capacitor plates of a capacitive structure to an initial displacement position; applying a known control voltage to at least one of the first and second capacitor plates to generate a first displacement; measuring a first capacitance of the capacitive structure at the first displacement; setting the first and second capacitor plates to a second displacement; measuring a second capacitance of the capacitive structure at the second displacement; determining the difference between the first and second capacitances to determine the difference between the first and second displacements; and adjusting the control voltage based on results of the determining operation.