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:
Jun. 25, 2024
Filed:
Apr. 14, 2022
Alps Alpine Co., Ltd., Tokyo, JP;
Tatsumi Fujiyoshi, Miyagi-ken, JP;
Alps Alpine Co., Ltd., Tokyo, JP;
Abstract
A capacitance detection device detecting a capacitance between a detection electrode and a detection target close to the detection electrode has: a first voltage output circuit that outputs a first alternating current voltage to be supplied to a shield electrode placed close to the detection electrode; a second voltage output circuit that outputs a second alternating current voltage with substantially the same frequency as the first alternating current voltage; and an operational amplifier that amplifies the difference in voltage between an inverting input terminal connected to the detection electrode and a non-inverting input terminal to which the second alternating current voltage is applied, and outputs the amplified difference in voltage. With the detection target close to the detection electrode, the second voltage output circuit outputs the second alternating current voltage adjusted so that an output voltage from the operational amplifier has a smaller amplitude than the first alternating current voltage.