Capacitive data card and reader thereof

• US 6,196,465 B1
• Filed: 07/31/1998
• Issued: 03/06/2001
• Est. Priority Date: 02/02/1996
• Status: Expired due to Fees

• Current Assignee: Tokyo Mechatronics Company Limited
• Original Assignee: Tokyo Mechatronics Company Limited
• Inventors: Awano, Kouichi
• Primary Examiner(s): Lee, Michael G
• Assistant Examiner(s): FUREMAN, JARED
• Application Number:
  US09/117,446
• Time in Patent Office: 949 Days
• Field of Search: 235/487, 235/492, 235/493, 235/449, 235/451, 902/25, 902/26, 902/27
• US Class Current: 235/487
• CPC Class Codes: G06K 19/08 using markings of different kinds or more than one marking of the same kind in the same record carrier, e.g. one marking being sensed by optical and the other by magnetic means
• CPC Class Codes: G06K 7/0004 Hybrid readers
• CPC Class Codes: G07F 7/086 by passive credit-cards adapted therefor, e.g. constructive particularities to avoid counterfeiting, e.g. by inclusion of a physical or chemical security-layer for security documents G07D7/00; for the reading of record-carriers in general G06K7/00; for the design of coded credit-cards G06K19/10

Abstract

The present invention relates to an improvement of a capacitive data card in which a fuse is built in a circuit of the card and a data bit is represented by a state of the fuse and to a reader of the capacitive data card. An object of the present invention is to provide a capacitive data card having high utility value and high reliability and a reader thereof. The capacitive data card comprises a capacitive memory area for storing bits relative to capacitive data in accordance with a resistance state of a fuse which is built in a circuit of the card, that is, a state for flowing an electric current through the circuit is set when the fuse is intact, and resistance of the circuit is substantially increased when the fuse blows out, and a magnetic memory area for storing magnetic data.

Claims

1. A capacitive data card comprising:

a magnetic memory area for storing first data; and

a capacitive memory area for irreversibly storing second data by a bit amount representative of a rough estimate of the remaining amount of said first data, wherein

said second data are changed by an amount larger than a minimal amount of change of said first data, and said second data are greater than said first data, or equal to said first data when the capacitive memory area is rewritten, and wherein

said minimal amount corresponds to an amount of adjustment of said first data.

2. A capacitive data card according to claim 1, wherein a layer constituting a magnetic memory area is formed on a surface of a substrate having the shape of a thin plate, and a layer constituting said capacitive memory area is superposed on a surface of the layer constituting said magnetic memory area.

3. A capacitive data card according to claim 1, wherein a layer constituting said capacitive memory area is formed on one side of a substrate having the shape of a thin plate, and a layer constituting said magnetic memory area is formed on the other side of said substrate.

4. A capacitive data card according to claim 1, wherein coating layers are superposed on a surface of a layer constituting said capacitive memory area and a surface of said magnetic memory area respectively.

5. A capacitive data card comprising:

an IC memory for storing first data; and

a capacitive memory area for irreversibly storing second data by a bit amount representative of a rough estimate of the remaining amount of said first data, wherein

said second data are changed by an amount larger than a minimal amount of change of said first data, and said second data are greater than said first data, or equal to said first data when the capacitive memory area is rewritten, and wherein

said minimal amount corresponds to an amount of adjustment of said first data.

6. A capacitive data card comprising:

one of a magnetic memory area and an IC memory for storing first data; and

a capacitive memory area for irreversibly storing second data by a bit amount representative of a rough estimate of the remaining amount of said first data, wherein

said second data are changed by an amount larger than a minimal amount of change of said first data, and said second data are greater than said first data, or equal to said first data when the capacitive memory area is rewritten, and wherein

said minimal amount corresponds to an amount of adjustment of said first data.

7. A capacitive data card reader according to claim 6, further comprising:

a first input output means for storing data in the capacitive memory area of the capacitive data card and/or reading the data stored therein;

a second input output means for storing data in said magnetic memory area and/or reading the data stored therein; and

checking means for judging that the capacitive data card is invalid irrespective of the data stored in one of said magnetic memory area and said IC memory when said second data read from said capacitive memory area is smaller than said first data read from the one of said magnetic memory area and said IC memory.