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US 7,405,612 B2Granted
Electronic device
AssigneeSeiko Instruments Inc.
InventorsYukimasa Minami, Yoshifumi Yoshida, Fumiyasu Utsunomiya
Life of this patent
Estimating the term…
Abstract
A Provided is an electronic device in which: alternating current power from an RF coil which receives an electromagnetic wave and converts the electromagnetic wave into power is rectified by a diode and a first capacitor; the power is stepped up by a charge pump type step-up circuit; the power stepped up by the step-up circuit is stored in a second capacitor by a charging and discharging circuit; and the stored power is supplied from the charging and discharging circuit to an RF transmission circuit.
Claims2
An electronic device, comprising:
- an RF coil for receiving an electromagnetic wave and converting the electromagnetic wave into electric power, the electromagnetic wave sufficient to generate a weak electric power that is less than a predetermined electric power;
- a step-up circuit coupled to the RF coil through a rectifying circuit including a diode and a first capacitor, activated in response to the electric power supplied from the RF coil and comprising a charge pump circuit wherein the predetermined electric power is obtained by feedback of the weak electric power converted by the rectifying circuit;
- a charging and discharging circuit connected to the step-up circuit, having a second capacitor for storing electric power stepped up by the step-up circuit, and controlling charge and discharge of the second capacitor;
- and
- an RF transmission circuit connected to the charging and discharging circuit.
2 more elements
Dependencies are inferred from the claim text.