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:
Apr. 25, 2006
Filed:
Sep. 06, 2002
Masami Yakabe, Tokyo, JP;
Naoki Ikeuchi, Tokyo, JP;
Masami Yakabe, Tokyo, JP;
Naoki Ikeuchi, Tokyo, JP;
Tokyo Electron Limited, Tokyo, JP;
Abstract
An electrostatic capacitance detection circuitcomprises an AC voltage generator, a first operational amplifierof which non-inverting input terminal is connected to specific potential (a ground in this example), a second operational amplifierthat includes a voltage follower, a resistance (R)connected between the AC voltage generatorand an inverting input terminal of the first operational amplifier, a resistance (R)connected between the inverting input terminal of the first operational amplifierand an output terminal of the second operational amplifier, and an impedance element (a capacitor)connected between an output terminal of the first operational amplifierand a non-inverting input terminal of the second operational amplifier, and a capacitor to be detectedis connected between the non-inverting input terminal of the second operational amplifierand specific potential. The electrostatic capacitance detection circuitand the capacitorare located adjacently.