JPS628283A - Information card - Google Patents

Abstract

PURPOSE:To remove a mutual interference by covering other various function circuit block excluding an antenna by a conductive film and connecting the conductive film to a grounding part. CONSTITUTION:An antenna 2 is formed in a periphery of a card substrate 1 by etching or printing on a conductor and respective circuit blocks 3 are formed on a center part thereof. Insulating films a and c have conductive films 17, 19 applied on their one surfaces and adhesives 20, 21 applied on their other surfaces. In forming the card, respective sheets a-c are superimposed to one another, centering the card substrate 1 on which the antenna and the various function circuit blocks are formed, so as to position through holes 22, 23 correspondingly to an earth pad 15 on their front and back surfaces, and oppose the bonding agents 20, 21 to the card substrate 1 in position, and thereafter, the bonding is performed through a thermocompression bonding or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to an information card having the size and thickness of a business card and having a wireless communication function.

Conventional Technology In recent years, so-called IC cards, which contain an IC chip the size of a business card and have identification functions (hereinafter referred to as ID functions) and memory functions, are being introduced into society. , communication of information with social systems using it is mostly done via a card reader/writer (hereinafter referred to as a card reader/writer), and the cardholder inserts the card into the card reader/writer. Otherwise, communication between the social system and the cardholder's information would not be possible. In order to deal with this problem, the concept of a card with a wireless communication function in which the card is equipped with a power supply and an antenna was developed, for example, in Japanese Patent Application Laid-Open No. 59-996.
Publication No. 89 U is shown in an information card having a communication function.

By the way, an extremely important functional element in a card having such a communication function is an antenna, and conventionally, such an antenna and other cards have been constructed.

Proposals for optimizing the card configuration by considering the relationship between the functional circuit blocks that make up the card are not approved. For example, in the above-mentioned document, Figure 1 shows a configuration diagram showing the relationship between the antenna and the functional circuit blocks that constitute other cards, in which the antenna is schematically shown as a single bar. However, there is no description of the interaction between the antenna having such a configuration and other functional circuit blocks.

Problems to be Solved by the Invention A card with a wireless communication function requires an antenna and other functional circuit blocks, especially an oscillator, an antenna driving power amplifier,
The receiving amplifier must be placed close to the receiving amplifier, and their mutual interference causes problems such as variations in the oscillation frequency of the oscillator and generation of parasitic oscillations in the power amplifier and the receiving amplifier. This tendency is particularly noticeable when considering the efficiency of the antenna and adopting an antenna that surrounds the card.

Means for Solving the Problems In order to solve the above problems, the present invention covers various functional circuit blocks other than the antenna configured on the card with a conductive film, and uses the conductive film to cover the various functional circuits described above. It is characterized by being electrically connected to the grounding part of the block.

Effects The present invention has the above-described configuration, and can eliminate mutual interference between the antenna and other functional circuit blocks configured on the card, especially the oscillator, antenna driving power amplifier, and reception amplifier, and is small, thin, and portable. An information card having a convenient wireless communication function can be realized.

Embodiment FIG. 1 is an embodiment showing in a perspective view the structure of a card with a wireless communication function, which transmits a code pre-applied to the card as electromagnetic waves in response to a calling signal.

In Figure 1, 1 is a card base material such as a printed circuit board, 2 is an antenna formed around the card base material 1 by etching or printing a conductor, and 3 is an antenna that includes each circuit block described below. 4 is an antenna switch circuit, and 5 is a reception area for receiving and demodulating electromagnetic waves modulated by a call code.

A demodulation circuit 6 compares the received and demodulated code with the code sent from the code generation circuit 8, and a code identification circuit 7 detects a match; 7 activates a buzzer in response to the output of the code identification circuit e; Buzzer drive circuit for making noise, 8
9 is the above-mentioned code generation circuit, 9 is a buzzer, 10 is a transmission power supply control circuit for operating the transmission circuit system in response to the output of the code identification circuit 6, 11 is an oscillator for generating a transmission carrier wave, and 12 is a code. a modulation circuit for modulating the carrier wave with the code obtained from the generation circuit 8; 13 a power amplification circuit for amplifying the modulated carrier wave; 14;
is a thin small battery for operating the above circuit section, 15
are ground pads formed on the front and back screens of the card base material 1 and connected to each other through through holes and connected to the ground of the above-mentioned functional circuit blocks.

As a means of organizing the above circuit blocks into a small and thin structure as shown in the figure, for example, a hole is made in the card base material 1 to accommodate an IC chip, passive components, etc., and the IC chip and components are accommodated therein. solder the electrode and the wiring pattern part formed on the card base material 1,
Connection means such as wire bonding and thermocompression bonding may be used.

When transmitting electromagnetic waves modulated by a code from the card, the antenna switch circuit 4 in FIG.
The antenna 2 is controlled so that the output of the antenna 2 is connected to the input of the reception demodulation circuit 6, and the input of the reception demodulation circuit 6 is connected at other times. When there is an electromagnetic wave, the card first receives the electromagnetic wave, identifies the code, sounds a buzzer, and sends out an electromagnetic wave modulated with the pre-assigned code.

1A and C are insulating films coated with a conductive film on one surface and an adhesive on the other, 16.18 is the above insulating film, IT, 19 is an insulating film. The conductive film 20 #21 is an adhesive formed on the other surface of each insulating film 15.17. 22
．． 23 is a through hole drilled through the insulating film 16.18 and the adhesive 20.21 so that the conductive film 17.19 is electrically connected to the ground pad 16; It is filled with a material forming a conductive film 17.19.

FIG. 2 shows this situation, and is a cross-sectional view taken along the Mu' line of the insulating film on which the conductive film of FIG. 1C is formed. Since the numbers in the second answer section are the same as those in FIG. 1, further explanation will be omitted.

As a means for forming a sheet as shown in FIG. After making holes and screen-printing a conductive paste in which powders such as carbon, silver, copper, etc. are dispersed, drying and curing may be used.

In order to improve electrical contact between the conductive film thus formed and the ground pad, it is useful to plate the surface of the ground pad 15 with gold or the like.

In forming the card, each of the sheets shown in FIG. There are through holes 22 on both sides as shown.
The three sheets shown in FIG. 1 a, b, and c are stacked with the adhesives 20 and 21 facing the card base material 1, and the adhesives 20 and 21 are placed in positions corresponding to the spuds 16. After that, it may be bonded by thermocompression bonding or the like.

FIG. 3 is a sectional view including the ground pad portion of the card constructed in this manner. Since the numbers of each part are the same as those in FIG. 1, further explanation will be omitted.

The conductive film 17.19 shown in Figures 1a and 3 is
It is arranged so as to face the area occupied by the all-function circuit block excluding the antenna shown in FIG.

In the above explanation, we did not mention batteries much, but there are various options such as adopting film-type solar cells, adopting arbitrary means of battery replacement, and even setting the battery compartment outside the area covered with a conductive film. It goes without saying that design changes can be easily made without departing from the spirit of the present invention.

In addition, in the embodiment, a buzzer is introduced to indicate that the assigned identification code has been received in order to facilitate confirmation of card operation, but even if this is omitted, it will not impede the overall operation. It is also obvious that this is not the case.

It goes without saying that the entire card thus formed may be covered with a thin insulating sheet to improve usability and usability.

Effects of the Invention As described above, according to the present invention, with a simple configuration, mutual interference between the antenna integrated on the card and various functional circuit blocks for configuring an information card having a wireless communication function can be avoided. This makes it possible to realize an information card that is small, thin, and conveniently portable and has a wireless communication function.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of the configuration of a card with a wireless communication function according to the present invention, and FIG. 2 is a cross-sectional view showing the structure of an insulating film coated with a conductive film used in the present invention.
FIG. 3 is a sectional view showing the structure of an information card constructed according to the present invention. 1...Card base material, 2...Antenna,
3...Occupied area of all functional circuit blocks except antenna, 16...Earth pad, 17.19.
... Conductive film, 22.23 ... Insulating film, through hole penetrating adhesive. Name of agent: Patent attorney Toshio Nakao and 1 other person1-
Ichiriki-rp G"-1-pHit5'J@!4, Isamu 2 Figure 3

Claims (1)

[Claims] An antenna, a transmission and reception circuit block, a code identification and code generation circuit block, and a transmission and reception control circuit block are formed in a thin planar shape on a flat circuit board, and the circuit blocks except the antenna are covered with a conductive film. , an information card characterized in that the conductive film is electrically connected to the ground portion of the various circuit blocks.