Data encryption device
First Claim
1. A portable data encryption device, comprising:
- a storage;
a primary cell including a power supply that is off in an initial state and that supplies power when switched on;
a wireless communication circuit which receives a wireless activation signal from an external terminal, and, in an operation using electromotive force generated by the received activation signal when the power supply from the primary cell is off, receives an encryption key from the external terminal and stores the received encryption key in the storage;
a switch which switches the power supply of the primary cell from off to on after the encryption key is stored in the storage by the wireless communication circuit;
an encryption circuit which reads the encryption key from the storage, encrypts data using the read encryption key, and stores the encrypted data in the storage, the encryption circuit operating using the power supplied from the primary cell after the power supply from the primary cell is switched on; and
a storage control unit configured to control access by the wireless communication circuit to the storage and access by the encryption circuit to the storage,wherein the storage control unit prohibits the wireless communication circuit from writing the encryption key in the storage, when the encryption circuit operates using the power supplied from the primary cell, andthe switch switches the power supply from the primary cell one way from off to on.
1 Assignment
0 Petitions
Accused Products
Abstract
A portable data sensor tag includes a memory, a data communication circuit which receives a wireless activation signal from an external terminal, and, in an operation using electromotive force generated by the received activation signal, receives an encryption key from the external terminal and stores the received encryption key in the memory. A power source supplies power, an insulator which switches a power supply from the power source from off to on, and a sensor circuit reads the encryption key from the memory, encrypts measured data using the read encryption key, and stores the encrypted measurement data in the memory. The sensor circuit operates using the power supplied from the power source after the power supply from the power source is switched on.
8 Citations
19 Claims
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1. A portable data encryption device, comprising:
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a storage; a primary cell including a power supply that is off in an initial state and that supplies power when switched on; a wireless communication circuit which receives a wireless activation signal from an external terminal, and, in an operation using electromotive force generated by the received activation signal when the power supply from the primary cell is off, receives an encryption key from the external terminal and stores the received encryption key in the storage; a switch which switches the power supply of the primary cell from off to on after the encryption key is stored in the storage by the wireless communication circuit; an encryption circuit which reads the encryption key from the storage, encrypts data using the read encryption key, and stores the encrypted data in the storage, the encryption circuit operating using the power supplied from the primary cell after the power supply from the primary cell is switched on; and a storage control unit configured to control access by the wireless communication circuit to the storage and access by the encryption circuit to the storage, wherein the storage control unit prohibits the wireless communication circuit from writing the encryption key in the storage, when the encryption circuit operates using the power supplied from the primary cell, and the switch switches the power supply from the primary cell one way from off to on. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)
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18. A control method for a portable data encryption device, the control method comprising:
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receiving a wireless activation signal from an external terminal by a wireless communication circuit of the portable data encryption device, the wireless communication circuit operating using electromotive force generated by the received activation signal when a power supply of a primary cell of the portable data encryption device is off; receiving an encryption key from the external terminal by the wireless communication circuit and storing the received encryption key by the wireless communication circuit in a storage of the portable data encryption device, when the power supply from the primary cell is off; switching the power supply from the primary cell from off to on by a switch of the portable data encryption device after the encryption key is stored in the storage by the wireless communication circuit, the power supply supplying power when switched on from an initial off state; and prohibiting the wireless communication circuit from writing the encryption key in the storage when an encryption circuit of the portable data encryption device operates using the power supplied from the primary cell, reading the encryption key by the encryption circuit from the storage after the power supplied from the primary cell is switched on from off by the switch, encrypting data by the encryption circuit, and storing the encrypted data by the encryption circuit in the storage, wherein the switch switches the power supply from the primary cell one way from off to on.
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19. A portable integrated circuit, comprising:
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a storage; a primary cell including a power supply that is off in an initial state and that supplies power when switched to an on state; a wireless communication circuit which receives a wireless activation signal from an external terminal, and, in an operation using electromotive force generated by the received activation signal when the power supply from the primary cell is off, receives an encryption key from the external terminal and stores the received encryption key in the storage; a switch which switches the power supply from the primary cell from off to on after the encryption key is stored in the storage by the wireless communication circuit; an encryption circuit which reads the encryption key from the storage, encrypts data using the read encryption key, and stores the encrypted data in the storage, the encryption circuit operating using the power supplied from the primary cell after the power supply from the primary cell is switched on; and a storage control unit configured to control access by the wireless communication circuit to the storage and access by the encryption circuit to the storage, wherein the storage control unit prohibits the wireless communication circuit from writing the encryption key in the storage, when the encryption circuit operates using the power supplied from the primary cell, and the switch switches the power supply from the primary cell one way from off to on.
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Specification