JP2001319208A - Non-contact data carrier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technology for performing tuning with a capacity pattern by forming the relevant capacity pattern on a non-contact data carrier device composed of a surface pattern only. SOLUTION: In the non-contact data carrier device, in which a resonance circuit is composed of an antenna coil 15 composed of a linear pattern circulated on an insulated base material, a capacity pattern 16 and an IC chip 8 packaged on both the terminals of the relevant antenna coil, for communicating with an external device in a resonance frequency that the relevant resonance circuit has, the antenna coil 15 is provided with the extended continuously circulating linear pattern, the relevant extension functions as a capacity pattern 16, and the resonance frequency can be controlled by controlling the length of the linear pattern in the relevant extended part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a non-contact data carrier device. More specifically, the present invention relates to a technique for adjusting a resonance frequency by adjusting a capacitance of a capacitor of a resonance circuit in a non-contact data carrier device.

[0002]

2. Description of the Related Art A non-contact data carrier device has a memory capable of storing various data and can be controlled by communicating with an external reader / writer in a non-contact manner. It has been used for various purposes such as management of products, prevention of theft of products, etc., production and distribution management, and the like. By the way, a non-contact data carrier device performs communication with an external device by using an electromagnetic wave having a natural resonance frequency of a data carrier.
In order to ensure the best communication state, it is necessary to perform accurate adjustment such that the frequency of the external device matches the resonance frequency of the data carrier.

[0003]

However, the conventional non-contact data carrier apparatus has no such wavelength adjustment (tuning) function, and has a problem that an optimum communication state cannot be obtained. Also, if you want to have a tuning function, form a capacitance pattern on both sides of the substrate,
There is a problem that the pattern needs to be adjusted, which complicates the manufacturing process of the data carrier. Therefore, the present invention has been completed by researching a data carrier structure that can easily be tuned even in a non-contact type data carrier device having a single-layer structure in which a pattern is formed only on the surface of a base material.

[0004]

SUMMARY OF THE INVENTION The first aspect of the present invention for solving the above-mentioned problems is as follows. An antenna coil composed of a linear pattern orbiting on an insulating base material, a capacitance pattern, and the antenna coil In a non-contact data carrier device that forms a resonance circuit with the IC chips mounted at both ends of the non-contact type and communicates with an external device at the resonance frequency of the resonance circuit, a linear pattern continuously circulating around the antenna coil is formed. A non-contact data carrier device characterized in that the extension is provided, the extension portion functions as a capacitance pattern, and the length of the linear pattern of the extension portion is adjusted to adjust the resonance frequency. is there. Since the contactless data carrier device is used, the wavelength can be easily adjusted.

[0005] In the above non-contact type data carrier device, the capacitance pattern composed of a linear pattern continuously circulating around the antenna coil extends along the inside of the antenna coil.
Also, it can be formed as a line pattern that is parallel to the antenna coil at substantially equal intervals, and the capacitance pattern consisting of a linear pattern continuously circulating around the antenna coil extends along the outside of the antenna coil and is substantially parallel to the antenna coil. Being formed as line patterns parallel at equal intervals,
Can also. Further, it is preferable that the cutting of one turn of the line pattern in the capacitance pattern gives a resonance frequency change of 0.05 to 0.1 MHz as an adjustment amount.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a non-contact data carrier device according to the present invention will be described with reference to the drawings. FIG.
FIG. 1 is a plan view showing an example of a non-contact data carrier device of the present invention. As shown in FIG. 1, the non-contact type data carrier device 10 includes an antenna coil 15 on one surface of an insulating base material 11 and a similar line pattern formed by extending the antenna coil, and functions as a capacitor. Pattern 16 and ICs mounted on both ends of the antenna coil
And a chip. Usually, a protective coating (not shown) is provided to cover the entire circuit of the insulating base material.

[0007] The antenna coil 15 is formed as a line pattern that goes around the periphery of the insulating base material 11. In FIG. 1, 6 counting from the periphery of the insulating base material 11.
The lines up to this correspond to the antenna coil 15, and the six lines inside it correspond to the capacitance pattern 16. In addition,
In FIG. 1, the illustration of the IC chip is omitted.

FIG. 2 is a block diagram of a non-contact type data carrier device.
It is a figure which expands and shows a C chip mounting part. IC chip 8
Is displayed only as a rectangular frame to make it easier to understand the state of the line pattern. A mark 21 is provided near the terminal 22A of the antenna coil 15 and the other terminal 22B.
A, 21B, 23A, 23B, etc. are formed. The marks 21A, 21B, 23A, 23B are circular marks 2
A straight line connecting the centers of 1A and 21B and a square mark 23
A straight line connecting the centers of A and 23B is orthogonal or substantially orthogonal.

In this non-contact type data carrier device 10, the antenna coil 15 and the marks 21A and 21B are covered with an insulating film made of an insulating resist material.
A, 22B and marks 23A, 23B
C chip 8 and terminals 22A, 2
Of the 2B, only a portion connected to a bump (not shown) of the IC chip 8 may be exposed, and another portion may be covered with an insulating film.

In mounting the IC chip 8, one of the square marks 23A and 23B is used, and the electrode of the IC chip 8 is bonded to the one mark and the terminals 22A and 22B, thereby connecting the IC chip 8 to three. It is possible to improve the stability by joining at a location. The bonding between the bumps of the IC chip and the terminals 22A and 22B may be performed by using an anisotropic conductive sheet or an anisotropic conductive adhesive, instead of using the molten bump method. The IC chip is flip-chip mounted.

In FIG. 2, the six line patterns on the inner peripheral side of the antenna coil, more precisely, the line pattern portions inwardly of the terminal 22A are portions to be the capacitance patterns 16. It can be understood that a capacitance is generated between each line pattern of the capacitance pattern and each line of the antenna coil 15 to increase the capacitance of the entire circuit. IC chip 8
In addition to its own capacitance (capacitance), there is also the stray capacitance of the circuit itself, so the L of the antenna coil and the combined capacitance C such as the stray capacitance of the capacitance pattern, IC chip, and circuit
Thus, a resonance circuit is formed and has a unique resonance frequency.

In the present invention, such a capacitance pattern 16
In this case, the capacitance of the entire circuit is adjusted by adjusting the length of the circuit, thereby adjusting (tuning) the resonance frequency. The capacitance pattern 16
It is preferable to form a line pattern along the antenna coil and parallel to the antenna coil at substantially equal intervals in order to stabilize the adjustment amount. In the case of FIG. 2, the capacitance pattern 16 is formed inside the antenna coil 15, but may be formed as a line pattern extending continuously to the terminal 22B and circling outward.

FIG. 3 is a diagram showing a specific example of cutting the capacitance pattern. As shown in FIG. 3, cutting 1, cutting 2, cutting 3, cutting 4, and cutting 5 are sequentially cut from the innermost line of the capacitance pattern 16 circling adjacent to the antenna coil. Even if the cutting is performed up to the cutting 5, the capacitance pattern for substantially one round still remains. In the case of this example, the line pattern for one round is removed by advancing the cutting step by step. However, if the cutting is performed at other corners, fine adjustment can be performed. The line pattern can be cut by a razor blade or the like, but cutting by a laser beam is also possible.

The capacitance between the line pattern of the capacitance pattern 16 and the antenna coil line is determined by the distance between the lines, the material of the insulating base material 11, the material of the protective coating, the size of the antenna coil 15,
The degree of change in capacitance due to one-step cutting is not uniform, but 13.56 M
At the resonance frequency of 1 Hz, the cutting of one line pattern turns
Providing a frequency change of about 0.05 to 0.1 MHz is appropriate as an adjustment amount. Usually, it is experimentally found that an appropriate communication state can be obtained within the range of the numerical value.

The base material used for the antenna sheet 11 is selected according to the purpose of use of the data carrier. Usually, a hard vinyl chloride sheet or polyester sheet (PET), which is insulative and also functions as a dielectric layer, or a polyimide or glass epoxy resin sheet is used. The thickness of the antenna sheet is about 20 to 150 μm, and preferably about 25 to 100 μm. Usually, a material obtained by laminating aluminum foil, copper foil, or iron foil having a thickness of 5 to 50 μm on the surface of the base material is used, and the aluminum foil, copper foil, or the like is etched to form an antenna coil portion or a capacitance pattern. However, it can also be formed by a printing method using a conductive ink such as an aluminum paste.

A similar substrate may be used for the protective sheet, but may be an inexpensive one such as paper. The data carrier sheet is generally used in the production or distribution process, and a decorative element is not so required except for being carried and used by a person such as a commuter pass. For a purpose other than a special purpose, a data carrier of a small size is desired, so that it is usually manufactured in a unit size of 50 mm × 50 mm or less.

The non-contact data carrier device 10 transmits and receives radio waves of a constant frequency by forming a resonance circuit by a coil and a capacitor. Generally, a frequency band of 125 kHz (medium wave), 13.56 MHz, and 2.45 GHz (microwave) is used.
At about 13.56 MHz, the communication distance is about 50 cm. With the data carrier device configuration as in the present invention, communication of about 60 cm is possible.

FIG. 4 is a graph showing a change in resonance frequency with respect to the number of cuts of the capacitance pattern. It is a measured value of a sample obtained from an example described later. From FIG. 4, it is recognized that the resonance frequency is increased by cutting the capacitance pattern. When the number of cuts is 0 (zero), the frequency of 13.37 MHz is 13.75 MHz when the number of cuts is 5, so that the frequency increases by 0.076 MHz on average for each cut.

FIG. 5 is a graph showing a change in capacitance with respect to the number of cuts of the capacitance pattern. This is a measurement of the capacitance of the antenna coil 15 itself,
It is not a measurement of a non-contact data carrier device with an IC chip mounted or a protective coating. With one cut,
Although the capacitance is reduced by about 0.5 to 1.0 pF, the capacitance does not become 0 (zero) even after cutting five times.
It is considered that there is a portion where the capacitance pattern 16 remains inside the chip mounting terminal (pad) 22A.

[0020]

EXAMPLES (Example) A 30 μm thick polyethylene terephthalate film (manufactured by Toray Industries, Inc.) having a thickness of 38 μm was used.
A non-contact data carrier device was prototyped using a base material in which a thick aluminum foil was laminated on one side. First, a casein-based resist is applied to the aluminum foil surface and dried.
The antenna coil 15 and the capacitance pattern 16 (6 turns of the antenna coil, 6 turns of the capacitance pattern) having the illustrated shapes were exposed and printed. After the development, etching was performed with an iron chloride solution to remove portions of the aluminum foil other than the portions that became the antenna coil and the capacitance pattern by etching.

The line width of the etched antenna coil linear pattern was 200 μm, and the line interval was 200 μm.
The capacitance pattern had the same line width and line interval. The IC chip 8 (size: 1.5 mm × 1.5 mm) was mounted on the terminals 22A and 22B at both ends of the antenna coil. The IC chip was mounted by applying an underfill agent and applying heat and pressure. Finally, the thickness, 100 μm
Was laminated as a surface protection sheet to complete a non-contact data carrier device.

The completed non-contact data carrier device is
Advance the capacitance pattern to cutting 3 and set the frequency to 13.56M
In Hz, a communication distance of about 60 cm could be obtained. Such a non-contact type data carrier device could be suitably used for sorting commuter passes, deliveries, and the like.

[0023]

Since the non-contact data carrier device of the present invention has the above-described configuration, even if the non-contact data carrier has a single-layer configuration in which the pattern is formed only on the surface of the base material, the tuning can be performed. Can be easily performed.
This makes it possible to easily adjust to the best communication state even if the characteristics vary depending on the production lot.

[Brief description of the drawings]

FIG. 1 is a plan view showing an example of a non-contact data carrier device of the present invention.

FIG. 2 is an enlarged view showing an IC chip mounting portion of the non-contact data carrier device.

FIG. 3 is a diagram showing a specific example of cutting a capacitance pattern. .

FIG. 4 is a graph showing a change in resonance frequency with respect to the number of cuts of the capacitance pattern.

FIG. 5 is a graph showing a change in capacitance with respect to the number of cuts of the capacitance pattern.

[Explanation of symbols]

 Reference Signs List 8 IC chip 10 Non-contact data carrier device 11 Insulating base material 15 Antenna coil 16 Capacitance pattern 21A, 21B Circular mark 22A, 22B Terminal 23A, 23B Square mark

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01Q 7/00 G06K 19/00 H H04B 5/00 K F term (Reference) 2C005 MA19 MA31 MA40 NA09 PA01 PA04 PA14 5B035 BA03 BB09 CA23 5J046 AA04 AB11 PA01 5K012 AA01 AA05 AB05 AC06

Claims (4)

[Claims] 1. A resonance circuit comprising an antenna coil formed of a linear pattern orbiting on an insulating base material, a capacitance pattern, and IC chips mounted on both ends of the antenna coil. In a non-contact data carrier device that communicates with an external device at the resonance frequency of the antenna device, a linear pattern continuously circulating around the antenna coil is provided to extend, the extended portion functions as a capacitance pattern, and A non-contact data carrier device, wherein the resonance frequency can be adjusted by adjusting the length of the linear pattern. 2. A capacitance pattern comprising a linear pattern continuously circulating around the antenna coil is formed as a line pattern extending along the inside of the antenna coil and parallel to the antenna coil at substantially equal intervals. Claim 1
A non-contact data carrier device according to claim 1. 3. A capacitance pattern comprising a linear pattern continuously circling around the antenna coil is formed as a line pattern extending along the outside of the antenna coil and parallel to the antenna coil at substantially equal intervals. Claim 1
A non-contact data carrier device according to claim 1. 4. The method according to claim 1, wherein cutting of one turn of the line pattern in the capacitance pattern is adjusted so as to give a resonance frequency change of 0.05 to 0.1 MHz. A non-contact data carrier device according to claim 1.