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:
Jul. 14, 2015
Filed:
Mar. 17, 2015
Murata Manufacturing Co., Ltd., Nagaokakyo-shi, Kyoto-fu, JP;
Naoto Ikeda, Nagaokakyo, JP;
Nobuo Ikemoto, Nagaokakyo, JP;
Naoki Gouchi, Nagaokakyo, JP;
Toshiyuki Nakaiso, Nagaokakyo, JP;
Katsumi Taniguchi, Nagaokakyo, JP;
Murata Manufacturing Co., Ltd., Kyoto, JP;
Abstract
In a communication circuit, an RFIC includes an IO terminal and a control IC includes an IO terminal. A variable capacitance element includes control terminals, a capacitance element with a capacitance value that is determined according to a control voltage, and a resistance voltage divider circuit configured to generate the control voltage by dividing a voltage inputted to the control terminals. One of the RFIC and the control IC supplies control data to the variable capacitance element via a signal line. The variable capacitance element, along with an antenna coil, constitutes an antenna circuit of an LC parallel resonance circuit, and sets a resonant frequency of the antenna circuit to be a predetermined frequency.