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:
Feb. 26, 2013
Filed:
Sep. 17, 2010
Shih-tzung Chou, Zhudong Township, Hsinchu County, TW;
Yong-nien Rao, Hsinchu, TW;
Yu Kuang, Hsinchu, TW;
Shih-Tzung Chou, Zhudong Township, Hsinchu County, TW;
Yong-Nien Rao, Hsinchu, TW;
Yu Kuang, Hsinchu, TW;
Raydium Semiconductor Corporation, Hsinchu County, TW;
Abstract
A capacitance measurement circuit includes an operation amplifier; a reference capacitor having a first terminal coupled to a first input terminal of the operation amplifier and a second terminal selectively coupled to a first or second reference voltage; a sensor capacitor having a first terminal coupled to a second input terminal of the operation amplifier and a second terminal selectively coupled to the first or second reference voltage; an approximation unit having an output terminal and an input terminal coupled to an output terminal of the operation amplifier; a conversion unit having an output terminal and an input terminal coupled to the output terminal of the approximation unit; and a coupling capacitor having a first terminal coupled to the first or second input terminal of the operation amplifier and a second terminal coupled to the output terminal of the conversion unit.