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US 6,807,400 B2Granted
Batteryless transponder
AssigneeTexas Instruments Deutschland GmbH
InventorThomas J. Flaxl
Life of this patent
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AssigneeTexas Instruments Deutschland GmbH
InventorThomas J. Flaxl
Estimating the term…
A batteryless transponder (10) which acquires its supply energy in that it rectifies an RF interrogation pulse transmitted by an interrogation device during a reception phase and that it uses the direct current so obtained to charge a storage device which serves as a supply voltage source during a transmission phase. In response to the reception of the RF interrogation pulse, the transponder transmits the information stored in it, wherein the coil of a tuned circuit serves as an antenna for both the reception of the interrogation pulse and the transmission of the information. The transponder contains a controllable switching device (14, 16, 18, 20, 22) which disconnects the tuned circuit (26) from the supply source during the transmission phase, and connects it to the supply voltage source only for a duration which is short as compared with a quarter period of the resonant oscillations, depending on the occurrence of each oscillation minimum of the resonant oscillations.
A Batteryless transponder which, in its reception phase, acquires its supply energy by the rectification of an RF interrogation pulse transmitted by an interrogation device and then stores it in a storage element serving as a supply voltage source during the transmission phase, and which, in response to the reception of the RF interrogation pulse, transmits information stored in it, wherein the coil of a tuned circuit having a resonant oscillation frequency serves as an antenna for both the reception of the interrogation pulse and the transmission of the information, characterized by a controllable switching device (14, 16, 18, 20, 22) which disconnects the tuned circuit (26) from the supply voltage source during the transmission phase, and connects it to the supply source only for a duration which is short as compared with a quarter period of the resonant oscillation frequency.
Dependencies are inferred from the claim text.