摘要 |
A physical quantity sensor includes: a substrate; a movable element; two fixed elements; a carrier wave application element for applying two carrier waves to the fixed elements; a signal application element for applying a middle voltage to the movable element; and a detection circuit for detecting a physical quantity. The detection circuit executes a first self diagnosis process when the signal application element further applies a first self diagnosis signal to the movable element. The first self diagnosis signal has a first frequency for obtaining a resonant magnification equal to or larger than 1.1 times with respect to a resonant frequency of the movable element, so that the movable element is resonated and almost contacts or press contacts one fixed element. The detection circuit determines whether a sticking phenomenon occurs when the signal application element applies the first self diagnosis signal.
|