Radio IC device and radio communication terminal

Patent metadata

Field	Value
Publication number	US-9336475-B2
Application number	US-201414337547-A
Country	US
Kind code	B2
Filing date	Jul 22, 2014
Priority date	Apr 25, 2012
Publication date	May 10, 2016
Grant date	May 10, 2016

Abstract

A radio IC device includes a radio IC element that includes an antenna terminal connected to an antenna element, and a ground terminal connected to a ground conductor provided integrally with the antenna element, and a circuit element that includes an impedance matching circuit connected to the antenna terminal of the radio IC element. The circuit element includes a first inductance element that defines the impedance matching circuit, and a second inductance element that is connected, as a high-frequency cutoff circuit for the radio IC element, to the ground terminal.

First claim

What is claimed is:

1. A radio IC device comprising:
a radio IC element including an antenna terminal connected to an antenna element, and a ground terminal connected to a ground conductor; and
a circuit board including a circuit element that includes an impedance matching circuit connected to the antenna terminal of the radio IC element; wherein
a portion of the ground conductor defines the antenna element, and the antenna terminal of the radio IC element is connected to the ground conductor via the impedance matching circuit; and
the circuit board further includes an inductance element that is provided separately from the impedance matching circuit and that is connected, as a high-frequency cutoff circuit for the radio IC element, between the ground conductor and the ground terminal.

2. The radio IC device according to claim 1 , wherein the circuit board is defined by a multilayer body including a plurality of stacked substrate layers.

3. The radio IC device according to claim 1 , wherein the impedance matching circuit is defined by another inductance element, and the inductance element and the another inductance element are not coupled to each other or are substantially not coupled to each other.

4. The radio IC device according to claim 1 , wherein the impedance matching circuit is defined by another inductance element, each of the inductance element and the another inductance element includes a coil, and winding axes of the coils of the inductance element and the another inductance element are arranged in different positions.

5. The radio IC device according to claim 1 , wherein the impedance matching circuit is defined by another inductance element, each of the inductance element and the another inductance element includes a coil, and winding axes of the coils of the inductance element and the another inductance element do not overlap in a plan view.

6. A radio IC device comprising:
a radio IC element including an antenna terminal connected to an antenna element, and a wired connection terminal connected to a different IC element by a wire; and
a circuit board including a circuit element that includes an impedance matching circuit connected to the antenna terminal of the radio IC element; wherein
the different IC element is connected to a ground conductor;
a portion of the ground conductor defines the antenna element, and the antenna terminal of the radio IC element is connected to the ground conductor via the impedance matching circuit; and
the circuit board further includes an inductance element that is provided separately from the impedance matching circuit and that is connected, as a high-frequency cutoff circuit for the radio IC element, between the different IC element and the wired connection terminal.

7. The radio IC device according to claim 6 , wherein the circuit board is defined by a multilayer body including a plurality of stacked substrate layers.

8. The radio IC device according to claim 6 , wherein the impedance matching circuit is defined by another inductance element, and the inductance element and the another inductance element are not coupled to each other or are substantially not coupled to each other.

9. The radio IC device according to claim 6 , wherein the impedance matching circuit is defined by another inductance element, each of the inductance element and the another inductance element includes a coil, and winding axes of the coils of the inductance element and the another inductance element are arranged in different positions.

10. The radio IC device according to claim 6 , wherein the impedance matching circuit is defined by another inductance element, each of the inductance element and the another inductance element includes a coil, and winding axes of the coils of the inductance element and the another inductance element do not overlap in a plan view.

11. The radio IC device according to claim 6 , wherein the inductance element is connected to a ground electrode of the radio IC element.

12. The radio IC device according to claim 6 , wherein the inductance element is connected to a power supply electrode of the radio IC element.

13. The radio IC device according to claim 6 , wherein the inductance element is connected to a clock electrode of the radio IC element.

14. A radio communication terminal comprising:
a radio IC device; and
a mother board including a ground conductor and an antenna element; wherein
the radio IC device includes a radio IC element that includes an antenna terminal connected to the antenna element and a wired connection terminal connected to a different IC element by a wire, and a circuit board including a circuit element that includes an impedance matching circuit connected to the antenna terminal of the radio IC element;
the different IC element is connected to the ground conductor;
a portion of the ground conductor defines the antenna element, and the antenna terminal of the radio IC element is connected to the ground conductor via the impedance matching circuit; and
the circuit board further includes an inductance element that is provided separately from the impedance matching circuit and that is connected, as a high-frequency cutoff circuit for the radio IC element, between the different IC element and the wired connection terminal.

15. The radio communication terminal according to claim 14 , wherein the circuit board is defined by a multilayer body including a plurality of stacked substrate layers.

16. The radio communication terminal according to claim 14 , wherein the inductance element is connected to a ground electrode of the radio IC element and the ground conductor.

17. The radio communication terminal according to claim 14 , wherein the inductance element is connected to a power supply electrode of the radio IC element and a power supply element provided on the mother board.

18. The radio communication terminal according to claim 14 , wherein the inductance element is connected to a clock electrode of the radio IC element and a host IC provided on the mother board.

19. The radio communication terminal according to claim 14 , wherein the inductance element is connected to a data electrode of the radio IC element and a host IC provided on the mother board.

20. A radio communication terminal comprising:
a radio IC device; and
a mother board including a ground and an antenna element; wherein
the radio IC device includes a radio IC element including an antenna terminal connected to an antenna element, a ground terminal connected to a ground conductor, and a circuit board including a circuit element that includes an impedance matching circuit connected to the antenna terminal of the radio IC element;
a portion of the ground conductor defines the antenna element, and the antenna terminal of the radio IC element is connected to the ground conductor via the impedance matching circuit; wherein
the circuit board further includes an inductance element that is provided separately from the impedance matching circuit and that is connected, as a high-frequency cutoff circuit for the radio IC element, between the ground conductor and the ground terminal.

Assignees

• Murata Manufacturing Co

Inventors

• Takeoka Makoto
• Dokai Yuya
• Murayama Hiromi

Classifications

• G06K19/07777

  the antenna being of the inductive type · CPC title

• G06K19/0726 Primary

  the arrangement including a circuit for tuning the resonance frequency of an antenna on the record carrier · CPC title

• H01Q1/2225 Primary

  used in active tags, i.e. provided with its own power source or in passive tags, i.e. deriving power from RF signal · CPC title

• H01Q23/00

  Antennas with active circuits or circuit elements integrated within them or attached to them · CPC title