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:
Aug. 30, 2022
Filed:
Oct. 28, 2020
Nf Holdings Corporation, Kanagawa, JP;
NF HOLDINGS CORPORATION, Kanagawa, JP;
Abstract
A capacitance measuring circuit measures an electrostatic capacitance formed between a first conductor that receive an AC signal and a second conductor. The capacitance measuring circuit includes an amplifier including an input and an output; signal detection means including a negative feedback unit that has a feedback capacitance and applies a negative feedback from an output of the amplifier to an input of the amplifier, wherein an input of the amplifier is connected to the second conductor and is virtually grounded by the negative feedback unit and an AC signal of an amplitude in a functional relation with the electrostatic capacitance is output; and measuring means that is connected to an output of the signal detection means and has a function of measuring at least an amplitude of an AC signal output of the signal detection means.