JP2005267656A - Noncontact type ic card - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a noncontact type IC card capable of preventing a storage area for storing data requiring confidentiality from being rewritten. <P>SOLUTION: This noncontact type IC card 600 carries out data communication by responding to data received from the outside, and is provided with: a memory 16 for storing the data requiring confidentiality; a memory 15 for storing data other than the data stored in the memory 16; and a main control circuit 2 for executing control for writing data in a relevant location of the memory 16 or the memory 15 according to the content of the data. The memory 16 allows the stored data requiring confidentiality to be erased by discharging charge charged in the memory 16. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a non-contact type IC card, and more particularly to a non-contact type IC card that can protect data stored therein and prevent falsification of data.

  Conventionally, there is a non-contact type IC card that performs data communication with an interrogator installed outside. For example, ski lift tickets, transportation commuter passes, prepaid cards, and the like are typical examples.

  FIG. 7 is a block diagram schematically showing a basic configuration of a conventional non-contact type IC card 900. A conventional non-contact type IC card 900 shown here is an IC card that performs data communication by a signal superposition method, and uses one or two or more frequency signals received from an interrogator (not shown) to power Supply and transmission / reception of information.

  The conventional non-contact type IC card 900 in FIG. 7 is an example of a non-contact type IC card that uses one frequency, and includes a tuning circuit 20, a rectifier circuit 21, an amplification demodulation circuit 22, a modulation amplification circuit 23, and SP / A PS conversion circuit 24 is provided.

  The tuning circuit 20 includes a coil L that functions as an antenna, and a capacitor C0. The rectifier circuit 21 rectifies the signal received by the tuning circuit 20, generates power, and supplies the power to each part of the non-contact type IC card 900.

  The amplification / demodulation circuit 22 amplifies and demodulates the data Q from the interrogator received by the tuning circuit 20. The signal output from the amplification / demodulation circuit 23 is SP converted by the SP / PS conversion circuit 24 and then output to the main control circuit 2 described later.

  Referring to FIG. 7, a conventional non-contact type IC card 900 further includes a main control circuit 2 and a memory 1.

  The main control circuit 2 processes the signal output from the SP / PS conversion circuit 24. The main control circuit 2 generates data DA to be stored in the memory 1 to be described later, and designates the position (address) of the memory 1 to which the data DA is written.

  The memory 1 includes a normal data storage area B1 and a data protection area B2. The memory 1 receives the data DA through the data line L2, and receives an address signal AD (write position) for writing the data DA through the address line L1. Here, in the data protection area B2, data for which secret maintenance is required to guarantee normal data communication and rewriting is prohibited is stored. An example of such data is an ID number in an ID card that holds personal information.

  Further, the main control circuit 2 reads data from the designated area B1 or data protection area B2 of the memory 1 according to the contents of the data Q received from the interrogator, and generates response data A based on the data. The response data A is PS converted by the SP / PS conversion circuit 24, then processed by the modulation amplification circuit 23, and transmitted from the coil L constituting the antenna to the interrogator.

  However, in the conventional non-contact type IC card 900, the data stored in the memory 1 can be easily rewritten (tampered) from other than the interrogator by decoding the protocol for performing data communication with the interrogator. Therefore, there is a problem that security is not guaranteed.

  Therefore, the present invention has been made to solve such a problem, and its purpose is a non-contact type IC that can prevent rewriting of a storage area in which data requiring secret maintenance is stored. To provide a card.

  In order to solve the above problems, a non-contact type IC card according to an aspect of the present invention is a non-contact type IC card that performs data communication in response to data received from the outside, and requires secret maintenance. A first storage means for storing data, a second storage means for storing data other than the data stored in the first storage means, and the corresponding first storage means or the first storage means depending on the contents of the data Control means for performing control for writing data at the position of the second storage means, and the first storage means stores the secret stored by discharging the charge charged in the first storage means. Data that requires maintenance can be erased.

  Preferably, the non-contact type IC card is a prepaid card or a lift ticket.

  Preferably, the first storage means is constituted by an EPROM, and the second storage means is constituted by an EEPROM or a flash memory.

  According to the present invention, by controlling the rewriting of data, it is possible to prevent rewriting of a storage area in which data requiring secret maintenance is stored.

[Embodiment 1]
In the first embodiment of the present invention, when data is written to the data protection area of the memory in the non-contact type IC card, the data stored in the data protection area is controlled by controlling the write address. It is possible to prevent rewriting.

  FIG. 1 is a diagram showing a configuration of a main part of a non-contact type IC card 100 according to Embodiment 1 of the present invention, and is common to the conventional non-contact type IC card 900 shown in FIG. Are denoted by the same reference numerals and reference numerals, and the description thereof is omitted. The data transmission / reception method of the non-contact type IC card to which the present invention is applied may be a signal superposition method or a signal separation method.

  The non-contact type IC card 100 shown in FIG. 1 is different from the conventional non-contact type IC card 900 in that when a data is written in the data protection area B2 of the memory 1, its designated write address. A state setting circuit 3 for controlling the address and an address non-selection circuit 4.

  With reference to FIG. 1, the structure of non-contact type IC card 100 in Embodiment 1 of the present invention will be described.

  The address non-selection circuit 4 receives the write enable signal RE output from the main control circuit 2 as an input and the address signal AD from the address line L1. Here, the address signal AD is a signal for designating the position of the data protection area B2 where the data DT on the data line L2 is written, and the write enable signal RE is a data write operation to the data protection area B2. The signal to be specified. The address non-selection circuit 4 outputs an address selection signal AC according to the address signal AD under the control of the state setting circuit 3 described later.

  The state setting circuit 3 is a circuit that controls the address non-selection circuit 4 described above.

  The address selection signal AC output from the address non-selection circuit 4 changes based on the state (active state / inactive state) of the state setting circuit 3. More specifically, when the state setting circuit 3 is in an active state, an address selection signal AC for selecting a position specified by the address AD as a position to write data is output, and when the state setting circuit 3 is in an inactive state. Outputs an address selection signal AC that inhibits writing to a position specified by the address signal AD (non-selected state).

  Data DT is written at a corresponding position in data protection region B2 based on address selection signal AC output from address non-selection circuit 4.

  Subsequently, the operation of the non-contact type IC card 100 according to the first embodiment of the present invention will be described.

  First, when the state setting circuit 3 is in an active state, an address selection signal AC for selecting a position specified by the address signal AD from the address non-selection circuit 4 receiving the write enable signal RE and the address signal AD. Is output. In this case, data DT is written at the corresponding position in data protection area B2.

  On the other hand, when the state setting circuit 3 is in the inactive state, the position specified by the address signal AD is set to the non-selected state from the address non-selecting circuit 4 that receives the write enable signal RE and the address signal AD. The address selection signal AC to be output is output. In this case, data DT is not written to data protection area B2.

  An example of such a state setting circuit 3 is one that uses a fuse. For example, when a fuse is used, data can be written into the data protection area B2 any number of times before the fuse is cut. However, when the fuse is cut, data in the data protection area B2 cannot be rewritten. Examples of the method for cutting the fuse include high voltage application, laser cutting, induction heating, and the like.

  That is, the non-contact type IC card 100 stores the data that needs the secret maintenance in the data protection area B2 by controlling the state of the state setting circuit 3 (for simplicity, this state is stored in the protected data storage state. After that, access to the data protection area B2 for the purpose of data rewriting can be made impossible.

  As described above, the contactless IC card 100 can control the address selection of the data protection area when the data writing operation is performed. Therefore, the data stored in the data protection area is altered. Can be prevented.

[Embodiment 2]
In the second embodiment of the present invention, as in the first embodiment of the present invention, in the non-contact type IC card, when data is written to the data protection area of the memory, by controlling the write address, The data stored in the data protection area can be prevented from being rewritten.

  FIG. 2 is a diagram showing a configuration of a main part of the non-contact type IC card 200 according to the second embodiment of the present invention. Components common to the non-contact type IC card 100 shown in FIG. The same reference numerals and reference numerals are used, and the description thereof is omitted.

  The non-contact type IC card 100 shown in FIG. 2 is different from the conventional non-contact type IC card 900 in that, when data is written in the data protection area of the memory, the designated write address is controlled. The command detection circuit 5 and the address non-selection circuit 6 are provided, and these circuits are controlled by a command output from the main control circuit 12.

  With reference to FIG. 2, the structure of non-contact type IC card 200 in Embodiment 2 of the present invention will be described.

  The address non-selection circuit 6 receives an address signal AD from the address line L1 as an input. Here, the address signal AD is a signal for designating the position of the data protection area B2 where the data DT on the data line L2 is written. The address non-selection circuit 6 outputs an address selection signal AC in response to the address signal AD under the control of a command detection circuit 5 described later.

  The command detection circuit 5 receives the address control command COM output from the main control circuit 12 and controls the address non-selection circuit 6. Here, the address control command COM is a command for permitting or prohibiting a data write operation to the data protection area B2 based on the address signal AD.

  The address selection signal AC output from the address non-selection circuit 6 changes according to the state of the command detection circuit 5. More specifically, when the command detection circuit 5 detects that the data protection area B2 is in a write-permitted state, an address selection signal AC that selects a position specified by the address AD as a position to write data. Is output. On the other hand, when it is detected that the data protection area B2 is in a write-inhibited state, an address selection signal AC that outputs a position specified by the address signal AD in a non-selected state is output.

  The data DT is written at a corresponding position in the data protection area B2 based on the address selection signal AC output from the address non-selection circuit 6.

  Subsequently, the operation of the non-contact type IC card 200 according to Embodiment 2 of the present invention will be described.

  When the address control command COM permitting data writing is output from the main control circuit 12, when this is detected by the command detection circuit 5, the position designated by the address signal AD is selected from the address non-selection circuit 6. An address selection signal AC is output. In this case, data DT is written at the corresponding position in data protection area B2.

  On the other hand, when the address control command COM prohibiting data writing is output from the main control circuit 12, when this is detected by the command detection circuit 5, the position designated by the address signal AD is detected from the address non-selection circuit 6. An address selection signal AC for making a non-selected state is output. In this case, data DT is not written to data protection area B2.

  In other words, the non-contact type IC card 200 controls the command detection circuit 5 based on a command output from the main control circuit 12 to store data that requires secret maintenance in the data protection area B2 (data It is possible to adjust the protection area B2 to be in a protected data storage state) and to make it impossible to access the data protection area B2 for the purpose of data rewriting.

  As described above, the non-contact type IC card 200 can control the address selection of the data protection area when the data writing operation is performed. Therefore, the data stored in the data protection area is altered. Can be prevented.

[Embodiment 3]
The third embodiment of the present invention prevents rewriting of data once stored in the data protection area by controlling access to the data protection area in accordance with the frequency for data communication in the non-contact type IC card. It is possible to do that.

  FIG. 3 is a diagram showing a configuration of a main part of the non-contact type IC card 300 according to Embodiment 3 of the present invention. Components common to the non-contact type IC card 100 shown in FIG. The same reference numerals and reference numerals are used, and the description thereof is omitted.

  The non-contact type IC card 300 shown in FIG. 3 is different from the conventional non-contact type IC card 900 in that it includes a frequency detection circuit 7 and an address non-selection circuit 8.

  With reference to FIG. 3, the structure of non-contact type IC card 300 in Embodiment 3 of the present invention will be described.

  The frequency detection circuit 7 is a circuit that detects the frequency of the received radio wave received by the tuning circuit 20, and includes a band-pass filter and a switch circuit in an interior not shown. When the carrier frequency of the received radio wave is the specific frequency F1, the frequency detection circuit 7 detects that the target radio wave has been received.

  The address non-selection circuit 8 receives an address signal AD from the address line L1 as an input and a write enable signal RE from the main control circuit 2. Here, the address signal AD is a signal for designating the position of the data protection area B2 where the data DT on the data line L2 is written.

  The address non-selection circuit 8 outputs the address selection signal AC in response to the address signal AD under the control of the frequency detection circuit 7. More specifically, when the frequency detection circuit 7 detects that the target radio wave (specific frequency F1) has been received, an address selection signal that selects a position specified by the address signal AD as a position to write data. In the case where AC is output and other than this (other than the specific frequency F1), an address selection signal AC that outputs a position specified by the address signal AD in a non-selected state is output.

  Data DT is written at a corresponding position in data protection area B2 based on address selection signal AC.

  The operation of the non-contact type IC card 300 will be specifically described with reference to FIG.

  When a radio wave having a carrier frequency of F1 is received, as described above, the address non-selection circuit 8 outputs an address selection signal AC for selecting a position specified by the address signal AD. In this case, the data DT is written at a corresponding position in the data protection area B2.

  On the other hand, when receiving a radio wave having a carrier frequency different from F1 and having the original frequency F0, the address non-selection circuit 8 outputs an address selection signal AC that makes the position designated by the address signal AD non-selected. In this case, data DT is not written in data protection area B2.

  That is, the non-contact type IC card 300 stores data that requires secret maintenance in the data protection area B2 by using different frequencies (the data protection area B2 is set in a protected data storage state). In addition, it is possible to make it impossible to access the data protection area B2 for the purpose of rewriting data.

  As described above, the non-contact type IC card 300 can control access to the data protection area according to the frequency of radio waves for data communication. Therefore, the data stored in the data protection area is altered. Can be prevented.

[Embodiment 4]
In Embodiment 4 of the present invention, when data is written to a data protection area of a memory in a non-contact type IC card, the write data is controlled to prevent alteration of the target data. Is possible.

  FIG. 4 is a diagram showing a configuration of a main part of the non-contact type IC card 400 according to the fourth embodiment of the present invention, and common components to the non-contact type IC card 100 shown in FIG. The same reference numerals and reference numerals are used, and the description thereof is omitted.

  The non-contact type IC card 400 shown in FIG. 4 is different from the conventional non-contact type IC card 900 in that it includes an input data fixing circuit 9 for controlling data to be written in the data protection area B2 of the memory 1. There is.

  With reference to FIG. 4, the structure of non-contact type IC card 400 in Embodiment 4 of the present invention will be described.

  The input data fixing circuit 9 is a circuit that fixes the state of each position in the data protection area B2 of the memory 1.

  The input data fixing circuit 9 receives data DT1 from the data line L2 as input, converts it, and outputs data DT2. The data DT2 becomes write data in the data protection area B2.

  It is assumed that the value of the data DT2 output from the input data fixing circuit 9 is determined based on the initial state of the data protection area B2. For example, if the state of all the bits in the data protection area B2 is “1”, the data DT2 always outputs a value of “0” having the opposite polarity. That is, when the data DT1 corresponding to the value “1” is output from the main control circuit 2, the data is not written to the data protection area B2.

  The operation of the non-contact type IC card 400 will be specifically described with reference to FIG.

  Assume that the initial state of each bit in the data protection area B2 of the memory 1 is set to “1” (the bit state is “1111”). In this case, only “0” data DT2 is output for each bit from the input data fixing circuit 9 that receives the data DT1.

  First, data requiring secret maintenance is written into the data protection area B2 (protected data storage state). This protected data storage state is assumed to be “1100”. As described above, the data DT2 output from the input data fixing circuit 9 is “0”. Therefore, a bit once in a “0” state cannot be returned to a “1” state. As a result, thereafter, the state (“1100”) of the data protection area B2 cannot be rewritten to “1101”, for example.

  That is, the data protection area B2 of the non-contact type IC card 400 functions as an OTP (non-volatile memory rewritable only once) ROM, and after storing data once in the data protection area, Even if rewriting is performed, the probability that the target data cannot be set becomes extremely high.

  As described above, the non-contact type IC card 400 can control data to be written to the data protection area when a data write operation is performed. Therefore, the data once stored in the data protection area can be rewritten. Use can be prevented.

[Embodiment 5]
In the fifth embodiment of the present invention, when data is written in a data protection area of a memory in a non-contact type IC card, tampering of the target data is prevented by controlling the write address. Is possible.

  FIG. 5 is a diagram showing a configuration of a main part of the non-contact type IC card 500 according to the fifth embodiment of the present invention. Components common to the non-contact type IC card 100 shown in FIG. The same reference numerals and reference numerals are used, and the description thereof is omitted.

  The non-contact type IC card 500 shown in FIG. 5 is different from the conventional non-contact type IC card 900 in that, when writing to the data protection area B2 of the memory 1, the designated write address is set. A state setting circuit 10 to be controlled and an address non-selection circuit 11 are provided.

  With reference to FIG. 5, the structure of non-contact type IC card 500 in Embodiment 5 of the present invention will be described.

  The address non-selection circuit 11 receives a write enable signal RE output from the main control circuit 2 as an input and an address signal AD from the address line L1. Here, the address signal AD is a signal for designating the position of the data protection area B2 where the data DT on the data line L2 is written. The address non-selection circuit 11 outputs an address selection signal AC in response to the address signal AD under the control of a state setting circuit 10 described later.

  The state setting circuit 10 is a circuit that controls the address non-selection circuit 11 described above.

  The address selection signal AC output from the address non-selection circuit 11 changes according to the state (active state / inactive state) of the state setting circuit 10. More specifically, when the state setting circuit 10 is in an active state, an address selection signal AC for selecting a position specified by the address signal AD as a data write position is output, and when the state setting circuit 10 is in an inactive state. Outputs an address selection signal AC for selecting a position other than the position specified by the address signal AD (or selecting none).

  The data DT is written at a corresponding position in the data protection area B2 based on the address selection signal AC output from the address non-selection circuit 11.

  Subsequently, the operation of the non-contact type IC card 500 according to the fifth embodiment of the present invention will be described.

  First, when the state setting circuit 10 is in an active state, an address selection signal AC for selecting a position specified by the address signal AD from the address non-selection circuit 11 that has received the write enable signal RE and the address signal AD. Is output. In this case, data DT is written at the corresponding position in data protection area B2.

  On the other hand, when the state setting circuit 10 is in the inactive state, a position different from the position specified by the address signal AD is selected from the address non-selection circuit 11 that has received the write enable signal RE and the address signal AD. An address selection signal AC is output (or none is selected). In this case, the data DT is not written at the target position in the data protection area B2.

  Such a state setting circuit 10 includes a fuse as described above.

  That is, the non-contact type IC card 500 controls the state of the state setting circuit 10 to store the data that needs to be kept secret in the data protection area B2 (protected data storage state), and then rewrite action is performed. Even if it occurs, the target data cannot be rewritten.

  As described above, the non-contact type IC card 500 can control the address selection of the data protection area when the data writing operation is performed, so that the data stored in the data protection area is rewritten. Can be prevented.

[Embodiment 6]
In Embodiment 6 of the present invention, an OTP (non-volatile memory rewritable only once) ROM is provided as a storage medium corresponding to a data protection area in a non-contact type IC card.

  FIG. 6 is a diagram showing a configuration of a main part of the non-contact type IC card 600 according to the sixth embodiment of the present invention, and is common to the configuration of the non-contact type IC card 100 shown in FIG. Constituent elements are denoted by the same reference numerals, and description thereof is omitted.

  The non-contact type IC card 600 shown in FIG. 6 is different from the conventional non-contact type IC card 900 in that a memory 15 and a memory 16 are provided in place of the memory 1.

  With reference to FIG. 6, the structure of non-contact type IC card 600 in Embodiment 6 of the present invention will be described.

  The memory 15 is a storage medium that stores rewritable data, and the memory 16 is a storage medium that stores data that needs to be kept secret.

  Specifically, the memory 15 is composed of a non-volatile memory that can be rewritten as needed, such as an EEPROM or a flash memory, and the memory 16 is composed of a memory that can be rewritten only once, as represented by an EPROM.

  Subsequently, the operation of the non-contact type IC card 600 according to the sixth embodiment of the present invention will be described. For simplicity, it is assumed that an EPROM is used as the memory 16.

  Data to be held output from the main control circuit 2 is stored in the memory 15 or the memory 16.

  In this case, the memory 16 is an EPROM, and once a memory cell (not shown) is charged, the charge cannot be discharged unless ultraviolet light is applied. Accordingly, assuming that the state in which the memory cell is charged is 1 state and the discharged state is regarded as 0 state, after the IC card 600 is sealed, the memory 16 is in a 0 state. Although the cell can be in the 1 state, a memory cell in the 1 state cannot be rewritten to the 0 state.

  Therefore, even if the data once stored in the memory 16 is rewritten, the possibility that the data is rewritten to the target data is extremely low.

  As described above, the non-contact type IC card 600 can keep data tampering efficiency very low by using the OTPROM as a medium for storing data to be protected.

It is the figure which showed the structure of the principal part of the non-contact-type IC card 100 in Embodiment 1 of this invention. It is the figure which showed the structure of the principal part of the non-contact-type IC card 200 in Embodiment 2 of this invention. It is the figure which showed the structure of the principal part of the non-contact-type IC card 300 in Embodiment 3 of this invention. It is the figure which showed the structure of the principal part of the non-contact-type IC card 400 in Embodiment 4 of this invention. It is the figure which showed the structure of the principal part of the non-contact-type IC card 500 in Embodiment 5 of this invention. It is the figure which showed the structure of the principal part of the non-contact-type IC card 600 in Embodiment 6 of this invention. It is the figure which represented roughly the structure of the conventional non-contact-type IC card 900. FIG.

Explanation of symbols

  1, 15, 16 Memory, 2, 12 Main control circuit, 3, 10 State setting circuit, 4, 6, 8, 11 Address non-selection circuit, 5 Command detection circuit, 7 Frequency detection circuit, 9 Input data fixing circuit, 20 Tuning circuit, C0 capacitor, L coil, 100-600,900 Non-contact type IC card.

Claims (3)

A non-contact type IC card that performs data communication in response to data received from the outside,
First storage means for storing said data for which secret maintenance is required;
Second storage means for storing data other than the data stored in the first storage means;
Control means for performing control for writing the data at the position of the first storage means or the second storage means corresponding to the content of the data,
The first storage means can erase the stored data requiring the secret maintenance by discharging the electric charge charged in the first storage means. card.   The non-contact type IC card according to claim 1, wherein the non-contact type IC card is a prepaid card or a lift ticket.   2. The non-contact type IC card according to claim 1, wherein the first storage means is constituted by an EPROM, and the second storage means is constituted by an EEPROM or a flash memory.

Images