Patent ID: 6668614
Filing Date: 2003-12-30
Classification: G01D,G01P

Abstract:
A capacitive type physical quantity detecting sensor comprising:a plurality of physical quantity detection portions for detecting a physical quantity, the plurality of physical quantity detection portions respectively including: a movable electrode that moves based on a physical quantity change; a fixed electrode disposed to face the movable electrode; a control signal generator for generating control signals; a C-V converter for outputting a voltage that corresponds to a change of a capacitance formed between the movable electrode and the fixed electrode; and a signal processing circuit for processing the output voltage from the C-V converter and for outputting a signal corresponding to the physical quantity change; wherein the control signal generator transmits a first signal to the movable electrode and the fixed electrode to detect the change in the capacitance formed between the movable electrode and the fixed electrode during a normal physical quantity detection timing interval, and transmits a second signal to the movable electrode and the fixed electrode to move the movable electrode for diagnosing a malfunction of each of the physical quantity detection portions in a self diagnosis timing interval, the control signal generator transmits the second signal to the movable electrode and the fixed electrode of each physical quantity detection portion at different timing intervals.