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:
Mar. 17, 2009
Filed:
Dec. 06, 2004
Rie Itoh, Osaka, JP;
Eiichi Sadayuki, Osaka, JP;
Rie Itoh, Osaka, JP;
Eiichi Sadayuki, Osaka, JP;
Panasonic Corporation, Osaka, JP;
Abstract
A frequency sensor includes at least one a resistor element and a capacitor. A frequency is detected according to a charging/discharging time to/from the capacitor, thereby realizing a frequency sensor with reduced power consumption and reduced circuit scale. Further, plural resistors and plural capacitors can be provided, along with switches connected to the respective resistors and capacitors. Additionally, a time constant can be adjusted after production, whereby variations in production can be reduced. Furthermore, a self-diagnosis circuit can be included for determining whether the frequency sensor itself operates normally or not. Thus, a highly-reliable frequency sensor can be realized.