Wireless IC device

• US 8,720,789 B2
• Filed: 08/28/2013
• Issued: 05/13/2014
• Est. Priority Date: 01/30/2012
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Dokai, Yuya
• Primary Examiner(s): St Cyr, Daniel
• Application Number:
  US14/011,823
• Publication Number:
  US 20130341415A1
• Time in Patent Office: 258 Days
• Field of Search: 235/492, 235/451, 235/462.13, 235/462.45
• US Class Current: 235/492
• CPC Class Codes: G06K 19/0701 at least one of the integrated circuit chips comprising an arrangement for power management
• 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 19/07767 the first and second communication means being two different antennas types, e.g. dipole and coil type, or two antennas of the same kind but operating at different frequencies
• CPC Class Codes: G06K 19/07777 the antenna being of the inductive type
• CPC Class Codes: G06K 19/07783 the coil being planar
• CPC Class Codes: G06K 19/07786 the antenna being of the HF type, such as a dipole
• CPC Class Codes: G06Q 20/341 Active cards, i.e. cards including their own processing means, e.g. including an IC or chip
• 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 1/36 Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewithH01Q1/08, H01Q1/14 take precedence

Abstract

A wireless IC device includes a wireless IC element, a power supply circuit substrate including a laminate of a plurality of base layers and a power supply circuit connected to the wireless IC element, and a radiating element connected to the power supply circuit. The power supply circuit includes a first coil element connected in series with the wireless IC element, and a second coil element connected in parallel with the wireless IC element. The first coil element and the second coil element are wound and arranged such that winding axes of the first and second coil elements coincide or substantially coincide with each other and directions of magnetic fields generated in the respective first and second coil elements are opposite to each other.

Claims

1. A wireless IC device comprising:

a wireless IC element;

a power supply circuit substrate including a laminate of a plurality of base layers, and a power supply circuit connected to the wireless IC element; and

a radiating element connected to the power supply circuit;

wherein

the power supply circuit includes a first coil element connected in series with the wireless IC element, and a second coil element connected in parallel with the wireless IC element; and

the first coil element and the second coil element are wound and arranged such that winding axes of the first and second coil elements coincide or substantially coincide with each other and directions of magnetic fields generated in the respective first and second coil elements are opposite to each other.

2. The wireless IC device according to claim 1, wherein the first coil element and the second coil element are arranged within the laminate such that the winding axis of each coil element extends along a lamination direction of the base layers.

3. The wireless IC device according to claim 1, wherein

the power supply circuit includes a first capacitor element and a second capacitor element which are connected between both end portions of the second coil element and the radiating element;

and

the second coil element and the first and second capacitor elements constitute a resonant circuit.

4. The wireless IC device according to claim 1, wherein the radiating element includes two radiating portions and connection portions.

5. The wireless IC device according to claim 4, wherein the two radiating portions are arranged to face each other across a gap at a center portion thereof in a longitudinal direction, and the connection portions are arranged to face the gap across which the radiating portions face each other.

6. The wireless IC device according to claim 1, wherein the radiating element includes a flexible metal film.

7. The wireless IC device according to claim 1, wherein the radiating element is a dipole radiating element.

8. The wireless IC device according to claim 1, further comprising a resin material arranged to cover the wireless IC element mounted on the power supply circuit substrate.

9. The wireless IC device according to claim 1, wherein the first coil element is a series inductance component on a side of the wireless IC device and the second coil element is a series inductance component on a side of the radiating element.

10. The wireless IC device according to claim 1, wherein a ratio of inductance values of the first and second coil elements is about 3:

1 or about 4;

1.

11. The wireless IC device according to claim 1, wherein the two radiating portions have a meander shape.

12. A wireless communication system comprising the wireless IC device according to claim 1.

13. A reader/writer apparatus comprising the wireless IC device according to claim 1.

14. An RFID device comprising the wireless IC device according to claim 1.