The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 14, 2010
Filed:
Jan. 17, 2008
Masashi Masuda, Nukata-gun, JP;
Junji Hayakawa, Okazaki, JP;
Masashi Masuda, Nukata-gun, JP;
Junji Hayakawa, Okazaki, JP;
DENSO CORPORATION, Kariya, JP;
Abstract
A capacitive physical quantity detection device comprising a plurality of capacitive physical quantity sensors, wherein each sensor includes: a detection unit having a movable electrode and a fixed electrode; a C-V conversion circuit having a differential amplifier circuit, wherein a first input terminal of the differential amplifier circuit is coupled with the movable electrode, a second input terminal of the differential amplifier circuit inputs a reference voltage and a self-diagnosis voltage therein during a normal operation and a self-diagnosis operation, respectively, and the C-V conversion circuit outputs an output voltage; and a signal processing circuit that performs a signal processing of the output voltage, wherein the reference voltage in each sensor is substantially the same, the plurality of sensors performs the self-diagnosis operation simultaneously, and the self-diagnosis voltage in one of the sensors is a first self-diagnosis voltage that is different in magnitude from the self-diagnosis voltage in another one of the sensors.