Wireless IC device and electronic device

• US 7,830,311 B2
• Filed: 09/07/2007
• Issued: 11/09/2010
• Est. Priority Date: 07/18/2007
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Ikemoto, Nobuo, Ishino, Satoshi, Kimura, Ikuhei, Kataya, Takeshi, Kato, Noboru
• Primary Examiner(s): Le; HoangAnh T
• Application Number:
  US11/851,661
• Publication Number:
  US 20090021446A1
• Time in Patent Office: 1,159 Days
• Field of Search: 343/700.MS, 343/702, 343/895
• US Class Current: 343/700.0MS
• CPC Class Codes: G06K 19/07749 the record carrier being capable of non-contact communication, e.g. constructional details of the antenna of a non-contact smart card
• CPC Class Codes: G06K 19/0775 arrangements for connecting the integrated circuit to the antenna
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/16227 the bump connector connecting to a bond pad of the item
• CPC Class Codes: H01Q 1/2225 used in active tags, i.e. provided with its own power source or in passive tags, i.e. deriving power from RF signal
• CPC Class Codes: H01Q 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142
• CPC Class Codes: H01Q 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop
• CPC Class Codes: H05K 1/0239 Signal transmission by AC coupling
• CPC Class Codes: H05K 1/0243 Printed circuits associated with mounted high frequency components
• CPC Class Codes: H05K 1/141 One or more single auxiliary printed circuits mounted on a main printed circuit, e.g. modules, adapters H05K1/142 and H05K1/147 take precedence
• CPC Class Codes: H05K 1/16 incorporating printed electric components, e.g. printed resistor, capacitor, inductor
• CPC Class Codes: H05K 2201/10098 Components for radio transmission, e.g. radio frequency identification [RFID] tag, printed or non-printed antennas

Abstract

A wireless IC device includes a wireless IC chip for processing a transmission/reception signal, a printed wiring circuit board on which the wireless IC chip is mounted, a ground electrode disposed on the circuit board, and a substantially loop-shaped electrode that is electrically conducted to the wireless IC chip and disposed on the circuit board so as to be coupled to the ground electrode by an electromagnetic field. The ground electrode is coupled to the wireless IC chip via the substantially loop-shaped electrode to transmit/receive a radio frequency signal. A feeder circuit board including a resonant circuit and/or a matching circuit may be interposed between the wireless IC chip and the substantially loop-shaped electrode.

Claims

1. A wireless IC device comprising:

a wireless IC chip arranged to process a transmission/reception signal;

a circuit board on which the wireless IC chip is mounted;

a ground electrode disposed on the circuit board; and

a substantially loop-shaped electrode that is electrically conducted to the wireless IC chip, and disposed on the circuit board so as to be electromagnetically coupled to the ground electrode;

wherein

the substantially loop-shaped electrode has an impedance matching function;

the ground electrode is arranged to receive a radio frequency signal and to radiate a response signal from the wireless IC chip; and

the substantially loop-shaped electrode is arranged to transmit the radio frequency signal received by the ground electrode to the wireless IC chip and to transmit the response signal from the wireless IC chip to the ground electrode.

2. The wireless IC device according to claim 1, wherein the substantially loop-shaped electrode and the ground electrode are disposed on the same principal surface of the circuit board.

3. The wireless IC device according to claim 1, wherein at least one of the substantially loop-shaped electrode and the ground electrode is disposed in an inner portion of the circuit board.

4. The wireless IC device according to claim 1, wherein the substantially loop-shaped electrode and the ground electrode are arranged in a state insulated from each other.

5. The wireless IC device according to claim 1, wherein the substantially loop-shaped electrode and the ground electrode are arranged in a state electrically conductive to each other.

6. The wireless IC device according to claim 1, wherein the substantially loop-shaped electrode includes an impedance matching function.

7. An electronic apparatus comprising the wireless IC device according to claim 1.

8. A wireless IC device comprising:

an electromagnetic coupling module having a wireless IC chip arranged to process a transmission/reception signal, and a feeder circuit board including an inductance element, the inductance element being connected to the wireless IC chip in an electrically conductive state;

a circuit board on which the electromagnetic coupling module is mounted;

a ground electrode disposed on the circuit board; and

a substantially loop-shaped electrode that is electrically conducted to the feeder circuit board, and disposed on the circuit board so as to be electromagnetically coupled to the ground electrode;

wherein

the substantially loop-shaped electrode has an impedance matching function;

the ground electrode is arranged to receive a radio frequency signal and to radiate a response signal from the wireless IC chip; and

the substantially loop-shaped electrode is arranged to transmit the radio frequency signal received by the ground electrode to the wireless IC chip and to transmit the response signal from the wireless IC chip to the ground electrode.

9. The wireless IC device according to claim 8, further comprising a resonant circuit disposed in the feeder circuit board.

10. The wireless IC device according to claim 9, further comprising an external electrode disposed on a surface of the feeder circuit board, the external electrode being coupled by an electromagnetic field to the resonant circuit and electrically conducted to the substantially loop-shaped electrode.

11. The wireless IC device according to claim 8, further comprising a matching circuit disposed in the feeder circuit board.

12. The wireless IC device according to claim 11, further comprising an external electrode disposed on a surface of the feeder circuit board, the external electrode being coupled by an electromagnetic field to the matching circuit and electrically conducted to the substantially loop-shaped electrode.

13. The wireless IC device according to claim 8, wherein the feeder circuit board is defined by a multilayer board.

14. The wireless IC device according to claim 8, wherein the feeder circuit board is defined by a flexible board.

15. A wireless IC device comprising:

a wireless IC chip arranged to process a transmission/reception signal;

a circuit board on which the wireless IC chip is mounted;

a ground electrode disposed on the circuit board; and

a substantially loop-shaped electrode that is electrically conducted to the wireless IC chip, and disposed on the circuit board so as to be electrically connected to the ground electrode;

wherein

the substantially loop-shaped electrode has an impedance matching function;

the ground electrode is arranged to receive a radio frequency signal and to radiate a response signal from the wireless IC chip; and

the substantially loop-shaped electrode is arranged to transmit the radio frequency signal received by the ground electrode to the wireless IC chip and to transmit the response signal from the wireless IC chip to the ground electrode.

16. A wireless IC device comprising:

an electromagnetic coupling module having a wireless IC chip arranged to process a transmission/reception signal, and a feeder circuit board including an inductance element, the inductance element being connected to the wireless IC chip in an electrically conductive state;

a circuit board on which the electromagnetic coupling module is mounted;

a ground electrode disposed on the circuit board; and

a substantially loop-shaped electrode that is electrically conducted to the feeder circuit board, and disposed on the circuit board so as to be electrically connected to the ground electrode;

wherein

the substantially loop-shaped electrode has an impedance matching function;

the ground electrode is arranged to receive a radio frequency signal and to radiate a response signal from the wireless IC chip; and

the substantially loop-shaped electrode is arranged to transmit the radio frequency signal received by the ground electrode to the wireless IC chip and to transmit the response signal from the wireless IC chip to the ground electrode.