Circuit and method for using capacitive touch to further secure information in rfid documents
AssigneeTexas Instruments Incorporated
InventorsPrasanna Parthasarathy, Michael L Mitchell
Life of this patent
Estimating the term…
Abstract
A system for limiting access to confidential information including storage circuitry for storing the confidential information. An access enabling circuit allows access to the storage circuitry in response to a first level of an enabling signal. A processor generates the enabling signal for a predetermined amount of time in response to sensing of a change of a predetermined value that is produced in response to an act by a person responsible for the confidentiality of the confidential information. The enabling signal assumes a second level after the predetermined amount of time to block access to the storage circuitry.
Claims18
A system, comprising:
- a radio frequency identification (RFID) chip, the RFID chip comprising:
- an RFID tag for storing information;
- a power input;
- and
- an enable input;
- and
- a processor coupled to the RFID chip, the processor configured to:
- operate in a first power mode in which the processor is configured to:
- monitor for energy received via an RFID signal;
- in response to the energy received via the RFID signal, transition to a second power mode in which the processor consumes more power than the first power mode;
- and
- operate in the second power mode in which the processor is configured to:
- in response to the transition to the second power mode, measure a capacitance at a capacitive sensor to sense a signal from a person;
- and
- send an enable signal to the enable input of the RFID chip in response to sensing the signal from the person.
A method comprising:
- storing, in a radio frequency identification (RFID) tag in an RFID chip, information, the RFID chip comprising a power input and an enable input;
- detecting energy received via a radio frequency signal by a processor operating in a first power mode;
- in response to the detecting of the energy, transitioning the processor from the first power mode to a second power mode;
- in response to transitioning the processor from the first power mode to the second power mode, measuring a capacitance at a capacitive sensor to sense a signal from a person;
- and
- sending, by the processor to the enable input of the RFID chip, an enabling signal, in response to sensing the signal from the person.
A microcontroller configured to:
- in a hibernation mode, monitor for a wake up signal from a radio frequency identification (RFID) reader;
- in response to the wake up signal, transition out of the hibernation mode;
- in response to the transition out of the hibernation mode, measure a capacitance of a capacitive sensor;
- and
- send, to an enable input of an RFID chip, an enable sign, in response to the measure of the capacitance.
Dependencies are inferred from the claim text.