JPH11306302A - Portable mobile terminal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mounting structure for a portable mobile terminal which protects an IC from dielectrostatic breakdown without degradation of a communication function, the increase of the cost or the degradation of the reliability. SOLUTION: An incorporated electric circuit is surrounded with a protective wiring 40 formed in almost the same plane to prevent a discharge current from the outside of a card from flowing to an IC chip and a coil. A portable mobile terminal using an electromagnetic wave as a radio communication means forms a cut part 41 in the protective wiring 40. The protective wiring 40 is formed by the same process as the formation of the coil and the internal wiring to avoid the increase of the cost.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a wireless IC card,
The present invention relates to a portable mobile terminal that performs information communication with a fixed terminal using wireless communication means such as an electromagnetic wave or an infrared ray such as a wireless multi-chip module.

[0002]

2. Description of the Related Art FIG. 3 shows how static electricity charged on a human body 100 is discharged to a ground 300 through a wireless IC card 10 when the wireless IC card 10 is brought close to a reader / writer device 200. The discharge current 400 enters the inside of the wireless IC card 10 from the end face thereof, and
Then, the IC 20 is destroyed and discharged to the reader / writer device 200 to reach the ground 300. As a general means for protecting the built-in IC against such static electricity, conventionally, (1)
A method has been adopted in which a case surface of a portable mobile terminal is covered with a metal plate or a conductive plastic member or the like so that a discharge current does not pass through an internal IC. In addition, as a countermeasure against static electricity of the IC itself, measures such as forming a protection diode in an input terminal of the IC have been adopted. Further, as means for increasing the electrostatic withstand capability of the IC itself, see Japanese Patent Application Laid-Open No. 05-085091.
No., Japanese Unexamined Patent Publication (Kokai) No. H10-209, there is a method described in Japanese Unexamined Patent Application Publication No. This method
(2) A ring-shaped conductor material serving as an electrostatic shield material is formed around the surface of the IC chip to be protected, and the discharge current becomes I
C does not reach the device inside.

[0003]

However, (1)
The method of covering the case surface of the portable mobile terminal with a metal plate or a conductive plastic member or the like is difficult to adopt for the portable mobile terminal using the electromagnetic wave as the communication means described in the example of FIG. This is because, by covering the surface of the case of the portable mobile terminal with a conductive material, the transmission efficiency of electromagnetic waves to the built-in coil is extremely reduced, and the communication function cannot be secured. The method of (2) forming a ring-shaped conductor material serving as an electrostatic shielding material around the surface of the IC chip is effective against static electricity using the end surface of the IC chip as a discharge path. No effect can be expected on the discharge current directly entering the IC electrode. On the other hand, since an area for attaching and forming an electrostatic shielding material on the surface of the IC chip is required, the IC
There is a concern that the chip size is increased, the chip cost is increased, and the reliability for breaking the IC chip is reduced.

SUMMARY OF THE INVENTION An object of the present invention is to realize a mounting structure of a portable mobile terminal that protects an IC from electrostatic destruction without lowering communication functions, increasing costs and lowering reliability.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a portable mobile terminal having radio communication means for transmitting electromagnetic waves or infrared rays and a semiconductor integrated circuit electrically connected to the radio communication means. Further, a conductor wiring surrounding the semiconductor integrated circuit and the wireless communication means is formed in a peripheral portion of the IC card.

Further, the semiconductor integrated circuit, the wireless communication means, and the conductor wiring are arranged on the same surface side of a substrate.

Further, the conductor wiring is an open circuit.

A coil serving as the wireless communication means;
The conductor wiring is formed by the same process.

More specifically, a portable mobile terminal such as a wireless IC card is connected to polyethylene terephthalate (hereinafter referred to as PET).
A protective wiring in which an IC sheet and a coil wiring and the like are arranged on substantially the same plane and an electric circuit is formed on the substantially same plane. To prevent the discharge current from the outside of the card from flowing into the IC chip and the coil to protect the card from electrostatic breakdown.

[0010] Further, in the case of a portable mobile terminal using electromagnetic waves as wireless communication means, a part or a plurality of protective wirings are cut out so as not to form a closed circuit so that the transmission efficiency of the electromagnetic waves to the built-in coil does not decrease. On the other hand, in the case of an IC card using infrared rays as a wireless communication means, it is not particularly necessary to cut out the protection wiring, and the protection wiring may be completely surrounded.

Further, by forming the protective wiring in the same process as the formation of the coil and the internal wiring, it can be formed without requiring extra cost.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A portable mobile terminal according to the present invention will be described below with reference to an embodiment of a wireless IC card using electromagnetic waves as wireless communication means. FIG. 1 is a front view (a) and a sectional view (b) of an embodiment according to the present invention, and FIG. 2 is an exploded perspective view thereof.

The wireless IC card 10 shown in FIGS.
20, the coil wiring 30 and the protection wiring 40 are formed by laminating with an adhesive 60 using an upper cover sheet 51 and a lower cover sheet 52 made of a PET resin sheet. At this time, the protection wiring 40 was formed outside the IC 20 and the coil wiring 30. That is, the protection wiring 40 is insulated from the IC 20 and the coil wiring 30 and is surrounded by these.
Was formed. Further, a notch 41 was formed in the protective wiring 40 so as not to form a closed circuit. Such a wireless IC
A portable mobile terminal such as a card has an IC 20 mounted inside.
And the coil wiring 30 and the like are surrounded by the protective wiring 40, the static wiring from the outside of the card is absorbed by the protective wiring 40, and the static electricity is discharged to the IC 20 and the coil wiring 30.
Can be protected from flowing into.

When the protection wiring 40 is formed by a closed circuit having no notch, the closed circuit functions as a coil and causes energy loss in the protection wiring 30, so that electromagnetic waves are used as wireless communication means. For portable mobile terminals, notches were provided in some or more of the protective wires to prevent the efficiency of electromagnetic wave transmission to the built-in coil from being reduced. In the case of the infrared type, since no electromagnetic wave is transmitted, the protective wiring 40 may form a closed circuit, and the notch 41 is not required. Next, a manufacturing process of the wireless IC card 10 will be described. First, the coil wiring 30 and the protection wiring 40 are simultaneously printed on the lower cover sheet 52 made of PET resin with a conductive paste, and are dried by heating.

Next, an anisotropic conductive sheet (not shown) is adhered to the position where the IC 20 is to be mounted, and the connection electrodes of the IC 20 are heated and pressed while facing the predetermined position of the coil wiring 30 pattern. The connection between the IC 30 and the IC 30 is established.

Finally, the wireless IC card 10 is formed by heating and pressing the upper cover sheet 51 on which the adhesive 60 made of a hot melt agent or the like has been applied in advance.

As described above, if the coil wiring 30 and the protection wiring 40 are formed by the same process, the wireless IC card 10 can be manufactured using the conventional process, so that the manufacturing process does not become complicated. An increase in manufacturing cost can be avoided.

As the lower cover sheet 51, the coil wiring 30 and the protection wiring 40 are not only formed by printing a conductive paste, but also made of PET resin to which a metal foil such as Al, Cu or the like is bonded in advance. The wiring pattern may be subjected to pattern etching. In this case, a similar card configuration can be adopted even in the case of a wireless IC card using infrared rays as communication means, which does not particularly require the coil wiring 30.

[0019]

As described above, the wireless IC according to the present invention
A portable mobile terminal such as a card can protect a static electricity from outside the card from flowing into an IC chip or a coil by forming a protective wiring.

[Brief description of the drawings]

FIG. 1 is a front view (a) and a cross-sectional view (b) of an embodiment according to the present invention.

FIG. 2 is an exploded perspective view of an embodiment according to the present invention.

FIG. 3 is a view showing a use state of a conventional wireless IC card.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Wireless IC card 20 ... IC 30 ... Coil wiring 40 ... Protective wiring 41 ... Notch 51 ... Upper cover sheet 52 ... Lower cover sheet 60 ... Adhesive 100 ... Human body 200 ... Reader / writer device 300 ... Ground 400 ... Discharge current

Claims (4)

[Claims] 1. A portable mobile terminal having wireless communication means such as electromagnetic waves or infrared rays and a semiconductor integrated circuit electrically connected to the wireless communication means, wherein the portable mobile terminal surrounds the semiconductor integrated circuit and the wireless communication means. A portable mobile terminal, wherein conductor wiring is formed in a peripheral portion of the IC card. 2. The portable mobile terminal according to claim 1, wherein said semiconductor integrated circuit, said wireless communication means, and said conductor wiring are arranged on the same surface side of a substrate. 3. The portable mobile terminal according to claim 1, wherein said conductor wiring is an open circuit. 4. The portable mobile terminal according to claim 1, wherein said coil serving as said wireless communication means and said conductor wiring are formed in the same process.