WO2001024108A1

WO2001024108A1 - Noncontact ic card capable of inhibiting data transmission

Info

Publication number: WO2001024108A1
Application number: PCT/JP1999/005272
Authority: WO
Inventors: Mitsuo Uetake
Original assignee: Fujitsu Limited
Priority date: 1999-09-28
Filing date: 1999-09-28
Publication date: 2001-04-05

Abstract

A non-contact IC card is protected from the leakage of the data stored in it due to illegal access. A noncontact IC card (1) is capable of transmitting data requested by an external device through a radio transmission line using the electric power obtained from the received electromagnetic radiation. The owner of the noncontact IC card (1) may give a command input section (2) permission to send the requested data. If the command input section is not permitted to send the requested data (2), a protection section (3) inhibits transmission of the data.

Description

Description Contactless IC card capable of preventing data transmission

The present invention relates to a technology related to a contactless IC card, and more particularly to a protection technology for preventing data stored in the contactless IC card from being leaked due to unauthorized access. Background art

IC cards, which have the appearance of a credit card that is easy to carry and have a built-in IC memory, are becoming popular in place of magnetic cards that perform magnetic recording. In particular, an IC card further equipped with a CPU for control can apply information security technology such as encryption, so that it can be used as a portable storage medium with excellent data security, for example, electronic management. Use in a wide variety of fields, such as money cards for entrance and exit, gates (keys) for entry / exit gates, media for identity verification in service systems of public institutions and various financial transactions, and alternative media such as transportation tickets. Examination is underway.

Among such IC cards, non-contact type IC cards that transmit and receive data between the IC card and the outside via a wireless transmission path using electric power obtained by receiving an incoming electromagnetic wave are provided on the card surface. Because there are no exposed electrical contacts, it has excellent mechanical strength and environmental resistance, and has the convenience that it is not necessary to secure a power source such as a battery.

Hereinafter, the general configuration and operation of the non-contact type non-contact type IC card system will be briefly described. Here, the international standard IS OZ IEC 1 An example is a proximity type contactless IC card with a built-in CPU that conforms to 4443. 1A and 1B show a schematic structure of a non-contact type IC card. FIG. 1A shows its physical structure, and FIG. 1B shows its electrical structure.

As shown in FIGS. 1A and 1B, the non-contact type IC card 100 has an IC chip 101 and an antenna coil 102 therein. Although not shown in FIG. 1A, as shown in FIG. 1B, the non-contact type IC card 100 also has a capacitor 103 therein, and the LC resonance circuit 104 is composed of the antenna coil 102 and the capacitor 103. Have been.

FIG. 2 is a block diagram showing details of an electrical internal configuration of the contactless IC card. The internal configuration of the contactless IC card can be broadly divided into an analog section 110 and a control section 120. In the figure, an analog section 110 includes an LC resonance circuit 104 composed of an antenna coil 102 and a capacitor 103, a protection circuit 111, a front end section 112, a power supply section 113, a transmission section 114, and a reception section. 115, and a clock detector 116. The control unit 120 includes a CPU 121, a ROM 122, a RAMI 23, an EEPROM 124, a serial / parallel conversion unit 125, a timer unit 126, and a circuit unit 127, and is connected via a bus (BUS) 128. Interconnected. Where antenna coil 1

The other components except for 02 and the capacitor 103 are shown in FIGS.1A and 1B.

It is configured on a 1C chip 101.

The values of the antenna coil 102 and the capacitor 103 constituting the LC resonance circuit 104 are based on the data between the non-contact type IC card and the reader / writer for this IC card, whose resonance frequency is defined by the aforementioned international standard. The frequency is set to 13.56 MHz, which is the frequency of the electromagnetic wave used for transmission and power transmission. The antenna coil 102 receives the electromagnetic wave of this frequency and outputs a high-frequency signal. The protection circuit 111 limits the amplitude of the high-frequency signal output from the LC resonance circuit 104 and prevents damage to other circuits due to overvoltage.

The front end unit 112 couples the power supply unit 113, the transmission unit 114, the reception unit 115, and the LC resonance circuit 104.

The power supply unit 113 rectifies the high-frequency signal output from the LC resonance circuit 104, further raises or lowers the voltage as needed, and then converts the high-frequency signal to a constant voltage. Supply power.

The transmission section 114 modulates the carrier signal of 847 KHz in the transmission data passed from the control section 120. In the contactless IC card system described here, a widely known method called the load switching method is used as the data transmission method from the contactless IC card to the IC card reader / writer. are doing. The details of the oral switching system will be described later.

The receiving unit 115 demodulates the high-frequency signal output from the LC resonance circuit 104, and passes the data transmitted from the IC card reader / writer to the control unit 120. The clock detection unit 116 detects an operation clock required by the control unit 120 from the high-frequency signal output from the LC resonance circuit 104.

The CPU 121 is a central processing unit that controls the operation of the entire non-contact type IC card according to a control program.

The ROM 122 is a read-only memory that stores control programs and data executed by the CPU 121 for controlling the entire apparatus.

The RAM 123 temporarily stores data, and is a random access memory used as a work area necessary for the CPU 121 to execute control processing.

The EEPROM 124 is an electrically erasable programmable ROM that stores data that needs to be saved even when power supply by electromagnetic waves is interrupted. I do.

The serial-to-parallel conversion unit 125 converts the transmission data generated by the control unit 120 from parallel to serial and passes it to the transmission unit 114, and controls the reception data passed from the reception unit 115 to serial-parallel conversion. Take it in part 120. The timer unit 126 counts the time required for the control processing executed by the CPU 121.

The miscellaneous circuit section 127 is another circuit such as an interface for controlling the operation of the analog section 110, for example.

Next, FIG. 3 will be described. FIG. 3 is a block diagram showing details of an electrical internal configuration of the reader / writer for the IC card, which is opposed to the above-mentioned non-contact type IC card. The internal configuration of this reader / writer can also be broadly divided into an analog section 200 and a control section 220. The analog section 200 includes an antenna coil 201, a capacitor 202, a protection circuit 203, a reflection detection section 204, a transmission modulation section 205, a clock generation section 206, a transmission signal amplification section 207, a reception signal amplification section 208, a reception detection section 209, The power supply unit 210 is configured. The control unit 220 includes a CPU 221 ROM 222, a RAM 223, an EEPROM 224, a serial / parallel conversion unit 225, a timer unit 226, and a miscellaneous circuit unit 227. I have.

The antenna coil 201 and the capacitor 202 form an LC resonance circuit 211 whose resonance frequency is 13.56 MHz, which is the frequency of electromagnetic waves defined by the above-mentioned international standard, similar to the resonance circuit of an IC card. The values of the antenna coil 201 and the capacitor 202 are set so as to be as follows.

The protection circuit 203 prevents the failure from spreading to each component of the analog unit 200 when a failure occurs in the antenna coil 201 or the like.

The reflection detection unit 204 converts the high-frequency signal output from the transmission signal amplification unit 207 to L This is to obtain the standing wave ratio (VS WR) of the standing wave generated from the traveling wave of the high-frequency signal and its reflected wave when flowing into the C resonance circuit 211. This is a necessary component for the load switching method, which is the data transmission method from the non-contact type IC force adopted in the IC force system. Here, the load switching method will be briefly described with reference to FIGS. In the load switching method, first, the resonance frequency of the LC resonance circuit 104 included in the non-contact type IC card is modulated by a signal having information of transmission data output from the transmission unit 114. In order to modulate the resonance frequency of the LC resonance circuit 104, for example, the voltage value applied to a variable capacitance diode (varicap) provided in the front end unit 112 is modulated to change the resonance frequency of the LC resonance circuit 112. The capacitance to be determined may be changed.

By the way, in a non-contact type IC card that is called a proximity type and has a communicable distance of about several tens of cm, the LC resonance circuit 104 of the non-contact type IC card located within the communicable distance and the reader / writer A relatively dense electromagnetic coupling occurs with the LC resonance circuit 2 1 1 on the side. At this time, when the resonance frequency of the LC resonance circuit 104 of the non-contact type IC card is changed, the impedance of the LC resonance circuit 211 seen from the transmission signal amplification unit 207 changes on the reader / writer side. . As described above, the contactless IC card modulates the resonance frequency with a signal having information on the transmission data, so the reader / writer has to change the impedance of the LC resonance circuit 211. If it is detected and demodulated, the original transmission data can be restored. The method of transmitting transmission data in this way is the load switching method. The change in impedance seen from the transmission signal amplifying section 207 generated in the LC resonance circuit 211 on the reader / writer side is based on the traveling wave of the high-frequency signal given to the LC resonance circuit 211 by the transmission signal amplifying section 207. The standing wave generated by the reflected wave from the LC resonance circuit 211 due to the impedance mismatch Can be observed as a change in the standing wave ratio. Therefore, in the reader / writer, the reflection detection unit 204 acquires a signal indicating the standing wave ratio of the high-frequency signal output from the transmission signal amplification unit 207, and demodulates the signal to obtain a non-contact IC card. Get transmission data from.

Continuing the description of FIG. The transmission modulation section 205 modulates the signal generated by the clock generation section 206 with the transmission data passed from the control section 220.

The clock generator 206 generates a carrier signal of 13.56 MHz, which is the frequency of the radio wave defined in the aforementioned international standard.

The transmission signal amplifying unit 2007 amplifies the high-frequency signal output from the transmission modulation unit 205.

The received signal amplifying unit 208 amplifies the received signal output from the reflection detecting unit 204, that is, the signal that changes according to the standing wave ratio of the high-frequency signal described above.

The reception detection section 209 detects the signal output from the reception signal amplification section 208, demodulates the transmission data from the original non-contact type IC card, and passes it to the control section 220. The function of each component of the control unit 220 is basically the same as the function of each component of the control unit 120 of the non-contact type IC card shown in FIG. 2, and a description thereof will be omitted. You.

The contactless IC card system shown in FIGS. 1, 2, and 3 has the configuration described above, and data is exchanged between the IC card and the reader / writer.

By the way, in such a non-contact type IC card system, communication is automatically started with the operating non-contact type IC card reader / writer as long as the communication distance is within the range, and data is exchanged. .

Therefore, even if the non-contact type IC card is left within the communicable distance with another operating reader / writer with the same data exchange There was a possibility that data was exchanged with the reader / writer.

This means that if a malicious third party installs a reader / writer that operates in accordance with the data exchange specifications of the contactless IC card, the data held by the contactless IC card will not May be accessed irrespective of the will of the holder of the card, and there is a risk of unauthorized use of the data stored on the contactless IC card by a third party, such as alteration / falsification. Was. Disclosure of the invention

In view of the above problems, an object of the present invention is to prevent data stored in an IC card from being leaked against unauthorized access to the contactless IC card.

The present invention is based on the premise of a non-contact type IC card that transmits data according to an external request to an external device via a wireless transmission path using power obtained by receiving an incoming electromagnetic wave. Specifically, it has the following configuration.

First, it obtains an instruction as to whether or not to permit transmission of data in response to an external request.

Then, when it is instructed not to permit the transmission of the data, the data is prevented from reaching the external device.

According to the above configuration, as long as the holder of the non-contact type IC card gives an instruction not to permit data transmission to the non-contact type IC card, the data is prevented from reaching the external device. Therefore, data leakage that is not intended by the holder is reliably prevented.

In the above-described basic configuration of the present invention, for example, if the power obtained by receiving an incoming electromagnetic wave is reduced, the power required to reach the data to an external device cannot be secured. Of data in response to external requests The arrival at the external device can be prevented. More specifically, if a power supply for data transmission is provided by using a resonance circuit that resonates at the frequency of the electromagnetic wave, for example, the resonance frequency of the resonance circuit is changed, or By reducing the Q factor of a circuit, its power can be reduced.

Here, in order to change the resonance frequency of the resonance circuit, for example, the capacitance component of the LC resonance circuit forming the resonance circuit may be changed. More specifically, the LC resonance circuit forming the resonance circuit may be changed. This can be realized by inserting a capacitor into the circuit. Further, in order to reduce the Q value of the resonance circuit, for example, a resistor may be inserted into the resonance circuit.

Also, in the above-described basic configuration of the present invention, for example, a light-receiving unit that receives external light, and a light-shielding unit that is movable and shields the external light received by the light-receiving unit depending on its position, are provided. May be configured to detect whether or not external light is received, and obtain the detection result as an instruction as to whether or not to permit transmission of data in response to an external request. According to the configuration, it is advantageous in terms of mechanical strength ゃ environment resistance as compared with a case where an instruction as to whether or not to transmit data is obtained using a switch that mechanically opens and closes a current path, for example.

Further, in the above-described basic configuration of the present invention, for example, a means for storing the content of the acquired instruction is provided, and the arrival of data in response to an external request is prevented according to the stored content. The above objectives can be achieved. In this configuration, in order to obtain an instruction from the IC card holder as to whether or not to permit data transmission, for example, a switch for opening and closing the current path is provided, and a change in the state of the switch is provided. The detected result is obtained as the instruction. Alternatively, in this configuration, a signal transmitted via a wireless transmission path and indicating an instruction as to whether or not to permit transmission of the data may be received and acquired. What The present invention also includes a reader / writer for a non-contact type IC card which transmits such a signal. BRIEF DESCRIPTION OF THE FIGURES

The present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

1A and 1B are diagrams showing a schematic structure of a non-contact type IC card.

FIG. 2 is a block diagram showing details of an electrical internal configuration of the contactless IC card.

FIG. 3 is a block diagram showing details of the electrical internal configuration of the IC card reader / writer.

FIG. 4 is a diagram showing the principle configuration of the present invention.

FIG. 5 is a diagram showing a schematic structure of a non-contact type IC card embodying the present invention. FIG. 6 is a diagram showing a first example of a cross section of a non-contact type IC card embodying the present invention at a slide switch knob portion.

FIG. 7 is a diagram showing a second example of a cross section of a non-contact type IC card embodying the present invention at a slide switch knob portion.

FIG. 8 is a diagram showing a first example of an electrical circuit configuration of a non-contact type IC card embodying the present invention.

FIG. 9 is a diagram showing a second example of the electrical circuit configuration of the non-contact type IC card embodying the present invention.

FIG. 10 is a diagram showing a third example of the electrical circuit configuration of the non-contact type IC card embodying the present invention.

FIG. 11 is a diagram showing a modified example of the electric circuit configuration when the second example shown in FIG. 7 is applied to FIG. FIG. 12 is a diagram showing a first modification of the third example shown in FIG.

FIG. 13 is a diagram showing a second modification of the third example shown in FIG.

FIG. 14 is a diagram showing a fourth example of the electric circuit configuration of the non-contact type IC card embodying the present invention.

FIG. 15 is a flowchart showing the processing contents of the switch state detection processing. FIG. 16 is a flowchart showing the contents of the data transmission process.

FIG. 17 is a flowchart showing the processing contents of the IC card operation mode setting processing.

FIG. 18 is a flowchart showing the processing content of the operation mode setting processing. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 4 is a diagram showing the principle configuration of the present invention. In the figure, a non-contact type IC card 1 embodying the present invention has an instruction obtaining unit 2 and a blocking unit 3.

The non-contact type IC card 1 has a function of transmitting data according to a request from the outside to an external device via a wireless transmission path by using power obtained by receiving an incoming electromagnetic wave.

The instruction obtaining unit 2 obtains an instruction from the holder of the non-contact type IC card 1 about whether to permit transmission of data in response to an external request. In an embodiment of the present invention to be described later, a switch or a phototransistor that opens and closes a current path or an instruction as to whether or not to permit transmission of data transmitted through a wireless transmission path is shown. The receiving unit that receives the signal corresponds to the instruction obtaining unit 2.

The blocking unit 3 blocks the data from reaching the external device when the instruction obtaining unit 2 is instructed not to permit transmission of data in response to an external request. In an embodiment of the present invention described later, a capacitor inserted into the LC resonance circuit is used. The blocking part 3 corresponds to a sensor resistor or a CPU that controls the operation of the entire non-contact type IC card.

Next, FIG. 5 will be described. FIG. 5 shows a schematic structure of a non-contact type IC card embodying the present invention. The non-contact type IC card described here is also a non-contact type non-contact type IC card with a built-in CPU, which is based on the international standard IS OZ IEC 1443, similar to the conventional technology described above. The load switching method shall be adopted as the data transmission method from the non-contact type IC card to the reader / writer for the non-contact type IC card.

As can be seen by comparing FIG. 5 with FIG. 1A, a non-contact type IC card (hereinafter, also simply referred to as “IC card”) 11 has an IC chip 12 and a It has an antenna coil 13. Further, the IC card 11 has a slide switch knob 14 which is a component related to the present invention. FIG. 6 is a diagram showing a first example of a cross section of the IC card 11 at the slide switch knob 14. The slide switch knob 14 is exposed from the opening provided in the IC card front cover 16 so that the holder of the IC card 11 can move the slide switch knob 14 right and left. The slide switch knob 14 is connected to a slide switch plate 15 that moves in response to an operation on the slide switch knob 14.

Here, the slide switch plate 15 is conductive, and when the slide switch plate 15 is moved to the right side of the figure, the wiring pattern 1 which is a part of the electric wiring inside the IC card 11 is shown. Conduct between 7a and 17b. That is, in the first example shown in FIG. 6, the slide switch plate 15 plays a role of a switch that mechanically opens and closes a current path.

FIG. 7 is a view showing a second example of the cross section of the IC card 11 at the slide switch knob 14. The slide switch knob 14 is similar to the first example Similarly, it is exposed on the surface from the opening provided in the IC card front cover 16 and can be moved right and left by the holder of the IC card 11. Further, the slide switch knob 14 is connected to a slide switch plate 15 that moves in response to an operation on the slide switch knob 14.

Here, the slide switch plate 15 is made of a material that does not transmit light, and when the slide switch plate 15 is moved to the right side in FIG. When moved, external light is blocked.

A phototransistor 18 is provided inside the IC card 11. When light is taken into the IC card 11, the phototransistor 18 turns on between the emitter and the collector, and conducts between the wiring patterns 17a and 17b. That is, in the second example shown in FIG. 7, the phototransistor 18 plays a role of a switch for opening and closing a current path depending on whether external light is taken in or not.

Next, FIG. 8 will be described. FIG. 8 is a diagram showing a first example of an electric circuit configuration of a non-contact type IC card embodying the present invention. In FIG. 5, the IC chip 12 and the antenna coil 13 are also shown in FIG. The capacitors 21 and 22 are both provided in the IC card 11. Further, the switch 23 employs one of the configurations shown in FIG. 6 or FIG.

Here, the same IC chip 102 as the IC chip 101 shown in FIG. 1B is used. Therefore, the IC chip 12 has circuits other than the LC resonance circuit 104 in FIG.

In FIG. 8, when the switch 23 is open, an LC resonance circuit is formed by the antenna coil 13 and the capacitor 21. The values of the antenna coil 13 and the capacitor 21 indicate that the resonance frequency of this LC resonance circuit is the value of the electromagnetic wave used for data transmission and power transmission between the IC card 11 and the reader / writer for the IC card 11. Set to be the frequency.

Now consider the case where switch 23 is closed. At this time, the capacitor 21 and the capacitor 22 are connected in parallel to form an LC resonance circuit of the antenna coil 13 and the capacitor 21 and the capacitor 22. Since the resonance frequency of the LC resonance circuit decreases in accordance with the capacitance of the capacitor 22, it deviates from the frequency of the electromagnetic wave transmitted from the reader / writer for the IC force 11. Due to the shift of the resonance frequency, the reception efficiency is significantly reduced, and the electric operation of the IC chip 12 is stopped because the power supply is reduced. As a result, data transmission from the IC card 11 to the reader / writer is prevented.

Here, the magnitude of the capacitance of the capacitor 22 with respect to the capacitor 21 is a sufficiently large resonance frequency with respect to the modulation depth of the resonance frequency of the LC resonance circuit generated for the load switching method. The value should be large enough to cause a drop.

In FIG. 8, the resonance frequency of the LC resonance circuit including the antenna coil 13 and the capacitors 21 and 22 indicates that the data transmission and the power transmission between the IC card 11 and the reader / writer for the IC card 11 are performed. The values of the antenna coil 13 and the capacitors 21 and 22 may be set so that the frequency of the electromagnetic wave used for the antenna becomes the same. In this case, the resonance frequency of the LC resonance circuit formed by the antenna coil 13 and the capacitor 21 when the switch 23 is opened becomes higher than the resonance frequency of the LC resonance circuit when the switch 23 is closed. Therefore, opening switch 23 makes it possible to shift the resonance frequency of the LC resonance circuit from the frequency of the electromagnetic waves transmitted from the IC card 11 reader / writer, and stops the electrical operation of IC chip 12 Can be done. As a result, data transmission from the IC card 11 to the reader / writer is prevented.

Next, FIG. 9 will be described. FIG. 9 shows a non-contact type IC card embodying the present invention. FIG. 3 is a diagram showing a second example of the electrical circuit configuration of FIG. In the figure, each component is the same as that shown in FIG. 8, and is denoted by the same reference numeral.

In the second example shown in FIG. 9, the capacitors 21 and 22 are connected in series. A switch 23 adopting one of the configurations shown in FIG. 6 or FIG. 7 is connected in parallel with the capacitor 22.

In FIG. 9, when the switch 23 is open, an LC resonance circuit is formed by the antenna coil 13, the capacitor 21, and the capacitor 22. The values of antenna coil 13, capacitor 21 and capacitor 22 are used when the resonance frequency of this LC resonance circuit is used for data transmission and power transmission between IC card 11 and reader / writer for IC card 11. Set to be the frequency of the electromagnetic wave.

Here, when switch 23 is closed, both terminals of capacitor 22 are connected, so that an LC resonance circuit of antenna coil 13 and capacitor 21 is formed. The capacitance of the capacitor 21 is larger than the combined capacitance when the capacitor 21 and the capacitor 22 are connected in series. Therefore, the resonance frequency of the LC resonance circuit when switch 23 is closed is lower than the resonance frequency of the LC resonance circuit configured when switch 23 is open, and is transmitted from the IC card 11 reader / writer. It deviates from the frequency of electromagnetic waves. Due to this shift in the resonance frequency, the reception efficiency is significantly reduced, and the IC chip 12 stops its electrical operation due to a decrease in power supply. As a result, data transmission from the IC card 11 to the reader / writer is prevented.

Here, the magnitude of the capacitance of the capacitor 22 with respect to the capacitor 21 is a sufficiently large resonance frequency with respect to the modulation depth of the resonance frequency of the LC resonance circuit generated for the load switching method. The value should be small enough to cause a drop.

In addition, as in the first example described above, in FIG. So that the resonance frequency of the LC resonance circuit with the capacitor 21 and the capacitor 22 becomes the frequency of the electromagnetic wave used for data transmission and power transmission between the IC card 11 and the reader / writer for the IC card 11. The values of the antenna coil 13 and the capacitors 21 and 22 may be set. In this case, the resonance frequency of the LC resonance circuit configured when switch 23 is opened is higher than the resonance frequency of the LC resonance circuit when switch 23 is closed. It is possible to shift the resonance frequency of the LC resonance circuit from the frequency of the electromagnetic wave transmitted from the reader / writer for the IC card 11, and as a result, data transmission from the IC card 11 to the reader / writer is prevented.

Next, FIG. 10 will be described. FIG. 10 is a diagram showing a third example of the electrical circuit configuration of the non-contact type I C card embodying the present invention. In the figure, the same components as those shown in FIG. 8 are denoted by the same reference numerals.

In the third example shown in FIG. 10, the LC resonance circuit composed of the antenna coil 13 and the capacitor 21 and the IC chip 12 are connected to each other by the reciprocal open / close states of the switch 23a and the switch 23b. A resistor 24 is inserted between them. When the resistor 24 is inserted between the LC resonance circuit and the IC chip 12, the high-frequency signal output from the LC resonance circuit is attenuated by the action of the resistor 24, and The electrical operation stops because the required power supply is reduced. As a result, data transmission from the IC card 11 to the reader / writer is prevented.

Here, if a circuit formed by connecting a resistor 24 in series with the parallel connection of the antenna coil 13 and the capacitor 21 is considered to be an LC resonance circuit, the resistor 24 will determine the Q value of this LC resonance circuit. It can be seen as lowering.

The switch 23a and the switch 23b can be realized by adopting any of the configurations shown in FIG. 6 or FIG. For example, if the switch is configured to switch the current path mechanically, two sets of the configuration shown in FIG. What is necessary is just to operate the switch knob 14 so that the opening / closing state of each switch is reversed. Also, it is easy to provide a switch for opening and closing two sets of current paths in accordance with the operation of the switch knob 14. If the current path is opened and closed according to the detection result of whether or not external light is received as shown in FIG. 7, for example, two sets of the configuration shown in FIG. If the electric circuit having one configuration used as 23b is changed to the circuit shown in FIG. 11, contradictory open / close states of the switch 23a and the switch 23b can be obtained.

Explaining the circuit shown in FIG. 11, when external light is detected and the phototransistor 18 is turned on, the base potential of the transistor 25 is reduced, the transistor 25 is turned off, and the wiring pattern 17a, Open between 17b. On the other hand, when the external light is cut off and the phototransistor 18 is turned off, the base potential of the transistor 25 rises, the transistor 25 is turned on, and the space between the wiring patterns 17a and 17b is changed. Connected.

By using this circuit, the switch 23a and the switch 23b shown in FIG. 10 can be realized by the configuration shown in FIG.

Further, the circuit shown in FIG. 10 can be modified to a circuit as shown in FIG. 12 or FIG.

In the circuit shown in Fig. 12, a circuit in which a switch 23 and a resistor 24 are connected in parallel is inserted between the IC chip 12 and the LC resonance circuit composed of the antenna coil 13 and the capacitor 21. The circuit shown in FIG. 13 is obtained by inserting a circuit in which a switch 23 and a resistor 24 are connected in parallel to an LC resonance circuit composed of an antenna coil 13 and a capacitor 21.

In each of the circuits shown in Figs. 12 and 13, opening switch 23 will insert resistor 24 into the LC resonance circuit consisting of antenna coil 13 and capacitor 21. The Q value of the LC resonance circuit decreases and the IC chip 12 The required power supply decreases, and its electrical operation stops. As a result, data transmission from the IC card 11 to the reader / writer is prevented. The circuits shown in FIGS. 12 and 13 are advantageous because they have fewer switches than the circuit shown in FIG.

Further, the resistor 24 may be deleted from the circuit shown in FIG. 12 or FIG. 13, so that the supply of power to the IC chip 12 can be completely stopped.

Next, FIG. 14 will be described. FIG. 14 is a diagram showing a fourth example of an electrical circuit configuration of a non-contact type IC card embodying the present invention. In the figure, the same components as those shown in FIG. 8 are denoted by the same reference numerals.

In FIG. 14, an IC chip 12 is connected to an LC resonance circuit composed of an antenna coil 13 and a capacitor 21, and a switch 23 is connected to the IC chip 12. Here, either of the configurations shown in FIG. 6 or FIG.

In the block diagram showing the details of the electrical internal configuration of the IC card shown in FIG. 2, the switch 23 is treated as one of the components of the miscellaneous circuit section 127, and its open / closed state is determined by the CPU. It is configured to be observable at 1 2 1.

In the fourth example shown in FIG. 14, the CPU 121, which controls the entire operation of the IC card 11, detects the open / closed state of the switch 23, and outputs a result indicating the detection result to the EEPROM. Stored in 1 2 4 Then, before sending data from the IC card 11 to the reader / writer, the data is checked, and when the holder of the IC card 11 indicates by the switch 23 that the data sending is not permitted. Will not send out the data overnight.

Next, a control program for causing the CPU 122 to perform the above-described control will be described. FIG. 15 is a flowchart showing the processing content of the switch state detection processing, which is a part of the processing realized by the CPU 121 executing the control program stored in the R〇M 122. This switch state detection processing is performed when the power is supplied from the LC resonance circuit to the IC chip 12 in FIG. 14 and the IC chip 12 is operating. This is executed as a part of the timer interrupt processing performed in step. Hereinafter, the processing content of the switch state detection processing will be described with reference to FIG.

First, in S1001, the CPU 121 detects the current open / closed state of the switch 23.

Next, in S1002, the CPU 121 determines whether or not the switch 23 is closed as a result of the detection in the previous step. Then, if the result of the determination is Yes, the flow proceeds to S1003, and after setting the switch status flag secured in a predetermined area of the RAM 123 to “1”, the flow proceeds to S1005. On the other hand, if the result of the determination in S 1002 is No, the flow proceeds to S 1004, the switch status flag is set to “0”, and then the flow proceeds to S 1005.

Thereafter, in S1005, the CPU 121 stores the current contents of the switch state flag in a predetermined area of the EEPROM 124, ends the current switch state detection processing, and shifts to execution of other processing.

The above processing is the switch state detection processing.

Next, FIG. 16 will be described. FIG. 16 is a flowchart showing the processing contents of the data transmission processing, which is a part of the processing realized by the CPU 121 executing the control program stored in the ROM 122. This switch state control process is executed when the CPU 121 detects another data transmission request transmitted from the reader / writer as a result of executing other control processes. Hereinafter, the contents of the data transmission processing will be described with reference to FIG. First, in S2001, the CPU 121 analyzes what is requested in the received data transmission request.

Subsequently, in S2002, the CPU 121 refers to the current value of the switch status flag stored in a predetermined area of the EEPROM 124.

Then, in S2003, the CPU 121 determines whether or not the current value of the switch status flag referred to in the previous step is “1”. If the result of the determination is Yes, the process proceeds to S2004, where data corresponding to the request analyzed in S2001 is read from the EE PROM 124, and the data is read via the serial / parallel conversion unit 125 to the analog unit 1 10 to be sent to the reader / writer. After that, the current data transmission processing ends, and other processing is executed. On the other hand, if the result of the determination in S2003 is No, the process of S2004 is terminated without executing the process of S2004, and the process proceeds to other processes.

The processing up to this point is the overnight transmission processing.

By the operation of the switch state control processing and the data transmission processing, when the holder of the IC card 11 indicates that the switch 23 has been opened and the data transmission has not been permitted, the transmission of the data is blocked. You.

Next, another example of the non-contact type IC card embodying the present invention (hereinafter, this example will be referred to as “fifth example”) will be described.

In the fifth example, first, the reader / writer for the IC card writes data indicating whether data transmission is permitted to the IC card. At this time, the IC card in which data indicating that data transmission is not allowed is written unless the data indicating that data transmission is allowed is written later. The electrical configuration of the IC card is the same as that of the conventional non-contact IC card shown in Fig. 1B. The only difference is that the control programs stored in ROM 1 in 2 are different. The details of the electrical internal configuration of the IC card reader / writer used in the fifth example are also the same as those of the conventional IC card reader / writer shown in FIG.

Here, a control program used to implement the fifth example will be described.

FIG. 17 shows a part of the processing performed by the CPU 221 executing the control program stored in the ROM 222 in the IC card reader / writer shown in FIG. 3. 5 is a flowchart showing the processing content of an operation mode setting process. In this switch state control process, the setting switch, which is one of the components of the miscellaneous circuit section 227, was operated, and the setting instruction regarding the IC card operation mode was issued by the user of the IC card reader / writer. Is executed when the CPU 2 21 detects. The contents of the IC card operation mode setting process will be described below with reference to FIG.

First, in S3001, the CPU 221 acquires the contents of the setting instruction regarding the operation mode of the IC card.

Then, in S302, it is determined what the setting contents of the operation mode acquired in the previous step are. As a result, if the instruction content is an instruction not to permit data transmission from the IC card, the process proceeds to S3003, and if the instruction content is an instruction to permit data transmission from the IC card, the process proceeds to S3005.

In step S303, a command indicating a command to disallow data transmission from the IC card is transmitted to the IC card.

In S304, it is determined whether or not a notification that the command transmitted in the previous step has been received has been returned from the IC card. If the notification has been received, the current IC card operation mode setting processing is performed. Terminates and moves on to other processing. On the other hand, as a result of the determination processing in S3002, when it is determined that the instruction to permit the data transmission from the IC card is performed by the user of the reader / writer for the IC card, in S3005, Data indicating an instruction to permit data transmission from the IC card is transmitted to the IC card.

In S306, it is determined whether or not a notification that the command transmitted in the previous step has been received has been returned from the IC card, and if the notification has been received, the current IC card operation mode setting processing is performed. Ends, and moves to the execution of other processing.

The above processing is the IC card operation mode setting processing.

Next, the control program of the IC card will be described.

FIG. 18 shows the operation mode setting process, which is a part of the process implemented by the CPU 121 executing the control program stored in the ROM 122 in the IC card shown in FIG. It is a flowchart which shows a process content. The operation mode setting process is performed when the CPU 12 1 detects that the data transmitted from the reader / writer received by the analog section 110 is data indicating an instruction to enable or disable data transmission. Be executed. Hereinafter, the processing content of the operation mode setting processing will be described with reference to FIG.

First, in S4001, the CPU 121 generates data notifying that the data indicating whether data transmission is possible has been received, passes the data to the analog unit 110, and sends the data to the reader / writer. It is sent to the address.

In S4002, the contents of the command sent from the reader / writer are analyzed, and if the content is a command permitting data transmission from the IC card, the process proceeds to S4003, and RAM1 is executed. After setting the switch status flag secured in the predetermined area of 23 to "1", the process proceeds to S405. On the other hand, if the result of the analysis in S4002 is an instruction to disallow data transmission from the IC card, the process proceeds to S404, and after setting the switch status flag to "0", Go to 4005. Thereafter, in S405, the CPU 122 stores the current contents of the switch status flag in a predetermined area of EEPR〇M124, which ends the current processing, and Move on to the execution of the process.

The processing described above is the operation mode setting processing.

The CPU 121 executes the data transmission processing shown in FIG. 16 in addition to the above-described operation mode setting processing. As a result, the operation of the fifth example described above in the IC card is realized.

In the fourth and fifth examples described above, when the instruction to send data from the IC card is not permitted, the sending of data from the IC card in response to an external data sending request is performed. Is not performed at all, but instead, data that is unrelated to the content of the request requested in the external data transmission request, for example, this IC card is not permitted to transmit data May be sent as data for notifying that the information is present.

As described above in detail, the present invention provides a non-contact type IC that transmits data according to an external request to an external device via a wireless transmission path by using power obtained by receiving an incoming electromagnetic wave. First, the card obtains an instruction as to whether or not to permit transmission of data in response to a request from the outside. The system is configured to block access to external devices.

As a result, as long as the holder of the non-contact type IC card instructs the non-contact type IC card not to permit data transmission, the data is prevented from reaching the external device, and the intention of the holder is prevented. This has the effect of reliably preventing unintended data leakage.

Claims

The scope of the claims

1. In a non-contact type IC card that transmits data corresponding to external requests to external devices via a wireless transmission path using power obtained by receiving an incoming electromagnetic wave,

Instruction acquisition means for acquiring an instruction as to whether or not to permit transmission of the data; and preventing the data from being transmitted to the external device when the instruction to not permit the data transmission is instructed. Blocking means to

Non-contact type IC card characterized by having:

2. The non-contact type IC force according to claim 1, wherein the blocking means blocks the arrival of the data by reducing the power.

3. It further comprises a resonance circuit that obtains the power by resonating at a frequency of the electromagnetic wave,

The blocking unit reduces the power by changing a resonance frequency of the resonance circuit;

3. The non-contact type IC card according to claim 2, wherein:

4. A resonance circuit for obtaining the electric power by resonating at a frequency of the electromagnetic wave,

The blocking means reduces the power by reducing a Q value of the resonance circuit.

3. The non-contact type IC card according to claim 2, wherein:

5. The instruction obtaining means includes:

A light-receiving unit that receives external light, and a light-shielding unit that is movable and shields external light received by the light-receiving unit depending on its position,

Detecting whether or not the light receiving unit is receiving external light; Get as an instruction as to whether to allow sending,

2. The non-contact type IC card according to claim 1, wherein:

6. The storage device further includes a storage unit that stores the content of the instruction acquired by the instruction acquisition unit, wherein the blocking unit prevents the arrival of the data according to the storage content of the storage unit.

2. The non-contact type IC card according to claim 1, wherein:

7. The instruction acquisition means,

It has a switch that opens and closes the current path,

Detecting a change in the state of the switch, and acquiring the detection result as an instruction as to whether or not to permit transmission of the data;

7. The non-contact type IC card according to claim 6, wherein:

8. The request range, wherein the instruction obtaining means receives and obtains a signal transmitted via a wireless transmission path and indicating whether or not to permit transmission of the data. The contactless IC card according to item 6.

9. Using the power obtained by receiving the arriving electromagnetic wave, transmit a signal addressed to a non-contact type IC card that transmits data in response to an external request to an external device via a wireless transmission path. In the contactless IC card reader / writer,

Signal generation means for generating a signal indicating an instruction as to whether or not to permit transmission of data in response to an external request;

Signal sending means for sending the signal to the non-contact type IC card via a wireless transmission path,

A reader / writer for a non-contact type IC card, comprising: