Invention Grant
- Patent Title: Communication circuit
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Application No.: US14255999Application Date: 2014-04-18
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Publication No.: US09026050B2Publication Date: 2015-05-05
- Inventor: Naoto Ikeda , Nobuo Ikemoto , Naoki Gouchi , Toshiyuki Nakaiso , Katsumi Taniguchi
- Applicant: Murata Manufacturing Co., Ltd.
- Applicant Address: JP Kyoto
- Assignee: Murata Manufacturing Co., Ltd.
- Current Assignee: Murata Manufacturing Co., Ltd.
- Current Assignee Address: JP Kyoto
- Agency: Keating & Bennett, LLP
- Priority: JP2011-234601 20111026
- Main IPC: H04B5/00
- IPC: H04B5/00 ; H04B5/02 ; H01Q7/00 ; G06K19/07 ; H01Q1/22

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.
Public/Granted literature
- US20140227978A1 COMMUNICATION CIRCUIT Public/Granted day:2014-08-14
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