Failure determination method of the capacitance sensor and capacitive sensor

摘要

Without providing a new circuit or the electrode, determine the abnormality of the capacitance sensor. A second potential different from the first potential and the first potential shield electrode disposed sensing electrodes for detecting the electrostatic capacity (2), in the vicinity of sensing electrodes (2) and (3), a shield electrode (3) shield drive circuit for applying by switching (31), the detection circuit outputs a detection signal corresponding to the capacitance detected by (2) the detection electrode (21), obtained from (21) the sensing circuit, (31) shield the shield drive means and the first detection signal corresponding to the capacitance detected by (2) the detection electrode when (31) is applied to the first potential shield electrode (3) shield drive means the presence or absence of abnormality shield electrode (3) sensing electrodes (or 2) based on the second detection signal corresponding to the capacitance detected by (2) the detection electrode when applying a second potential to the electrode and a determining circuit, and (6).