Device and method for checking the plausibility of an excitation signal for a rotation angle sensor

The present invention provides an apparatus and a method for checking the plausibility of an excitation signal. The apparatus is configured with: an input device (12) which is adapted to an input signal (52) based on the excitation signal to provide plausibilisierenden (51); an amplitude estimator (14) which is adapted to an amplitude estimate (53) for an amplitude of the excitation signal (51) based on the provided input signal (52) to determine; a phase estimator (16) which is adapted to receive a phase angle estimate (54) for a phase angle of the excitation signal (51) based on the provided input signal (52) to determine; a diagnostic device (18) which is adapted to generate a diagnostic signal (55) based at least on the determined amplitude estimate (53) and the determined phase angle estimate (54); and a Plausibilisierungseinrichtung (20) which is adapted, based on the diagnostic signal to check the plausibility of the excitation signal (51) (55) in response to a predetermined range of values ​​for the diagnostic signal (55).