Abstract: According to an embodiment, a power amplifier includes a variable passive element and a comparator. The variable passive element is connected directly or indirectly to a first terminal of a switch element and serves to increase or reduce a resonant frequency of the amplifier. The comparator compares a voltage of interest with a reference voltage and outputs a control voltage for the variable passive element based on a difference between the voltage of interest and the reference voltage.

Abstract: A foreign object detection device has a foreign object detector configured to detect a foreign object when a power receiver receives power from a power transmitter in a non-contact manner, the foreign object detector being arranged between the power receiver and the power transmitter, and a power control signal generator configured to generate a power control signal which controls the power transmitted from the power transmitter when the foreign object is detected by the foreign object detector

Abstract: According to one embodiment, there is provided a control apparatus for a first wireless power transmission apparatus and a second wireless power transmission apparatus. The first wireless power transmission apparatus includes a first inductor and an alternating-current signal source that supplies an alternating-current power to the first inductor. The second wireless power transmission apparatus includes a second inductor that receives the alternating-current power wirelessly from the first inductor. The position controller controls a phase relationship of current flowing in the first inductor and the second inductor such that attractive force or repulsive force is generated between the first and second inductors, and adjusts a relative position of the first inductor and the second inductor by use of the attractive force or the repulsive force.

Abstract: A clipping circuit includes: a first input terminal which receives a first signal, a second input terminal which receives a second signal, and a first variable resistive element which has a control terminal electrically connected to the second input terminal and which has a threshold, wherein first and second ends of the first variable resistive element are connected to first input terminal and a reference voltage, respectively. The clipping circuit also includes a second variable resistive element which has a control terminal electrically connected to the first input terminal and which has a threshold, wherein first and second ends of the second variable resistive element are connected to a second input terminal and the reference voltage, respectively.

Abstract: There is provided a wireless power transmission controller in which the input device receives first power information from a power transmitting device, indicating electric power transmitted by the power transmitting device, and second power information from a power receiving device, indicating electric power received by the power receiving device, the output device outputs a first control signal instructing a transmission voltage of the power transmitting device, and a second control signal instructing an impedance of the power receiving device, the control device performs raising control of transmission power of the power transmitting device by generating the second control signal so that a difference between the first and second power information becomes small, and generates the first control signal so that a difference between the first power information and a first target value or a difference between the second power information and a second target value becomes small.

Abstract: According to an embodiment, a power amplifier includes a variable passive element and a comparator. The variable passive element is connected directly or indirectly to a first terminal of a switch element and serves to increase or reduce a resonant frequency of the amplifier. The comparator compares a voltage of interest with a reference voltage and outputs a control voltage for the variable passive element based on a difference between the voltage of interest and the reference voltage.

Abstract: There is provided a power transmitting apparatus including: a power supply, a power transmitting inductor, a mutual coupling adjusting unit and a control unit, in which the power supply supplies AC power, the power transmitting inductor transfers the AC power to a power receiving apparatus through magnetic coupling with a power receiving inductor in the power receiving apparatus, the mutual coupling adjusting unit adjusts a relative position between the power transmitting inductor and the power receiving inductor, and the control unit controls the mutual coupling adjusting unit, based on a mutual coupling coefficient between the power transmitting inductor and the power receiving inductor.

Abstract: According to one embodiment, a wireless electric power transmission device supplies electric power, transmitted wirelessly from a first device, to a load circuit. The device includes a power receiving resonance unit, a detecting unit which detects electric power information corresponding to the electric power supplied to the load circuit, and a control unit. The control unit determines whether to adjust at least one of a resonant frequency of the power receiving resonance unit, an output frequency of an alternating current power supply of the first device, and a resonant frequency of a power transmitting resonance unit of the first device, on the basis of a relationship in terms of magnitude between first electric power information when the impedance is a first impedance and second electric power information when the impedance is a second impedance.

Abstract: There is provided a control device that estimates power transmission efficiency between a power transmitting unit and a power receiving unit. The power transmitting unit includes a first coil and a first capacitor connected to the first coil in parallel or in series. The power receiving unit includes a second coil and a second capacitor connected to the second coil in parallel or in series and receives electric power from the power transmitting unit through a coupling between the first coil and the second coil. The control device includes an estimator. The estimator compares a detected value of a first voltage or a first current at a first location in the power transmitting unit with a detected value of second voltage or second current at a second location in the power receiving unit and estimates the power transmission efficiency from the power transmitting unit to the power receiving unit.

Abstract: There provided a power receiving device connectable with a first load circuit operating according to AC power from a power transmitting device in which the power receiver receives the AC power from the power transmitting device via magnetic coupling, the impedance adjuster is capable of converting at least one of voltage and current of the AC power received at the power receiver, the controller controls increase in output voltage of the power transmitting device, the AC power is supplied to the first load circuit via the impedance adjuster when the first load circuit is connected to the power receiving device, and the controller controls the impedance adjuster such that an input impedance of the impedance adjuster is lower than an input impedance of the first load circuit during at least a part of a time period where the output voltage of the power transmitting device is increased.

Abstract: There is provided a clipping circuit in which a first input terminal receives a first signal, a second input terminal receives a second signal, a first variable resistive element has a control terminal electrically connected to the second input terminal and has a threshold, first and second ends of the first variable resistive element are connected to first input terminal and a reference voltage, respectively, the second variable resistive element has a control terminal electrically connected to the first input terminal and has a threshold, first and second ends thereof are connected to a second input terminal and the reference voltage, respectively, a first bias applying unit applies a bias voltage lower than the threshold to the control terminal regarding the first variable resistive element, and a second bias applying unit applies a bias voltage lower than the threshold to the control terminal regarding the second variable resistive element.

Abstract: In one embodiment, a wireless transmission apparatus is disclosed. The apparatus includes a generator unit, an amplitude adjuster unit, a phase adjuster unit, and a setting unit. The generator unit generates an amplitude control signal that minimizes an amplitude difference and a phase control signal that minimizes a phase difference in a state in which a power is set during an OFF period of a switch. The amplitude adjuster unit adjusts an amplitude of a feedback RF signal according to the amplitude control signal during an ON period of the switch. The phase adjuster unit adjusts a phase of a local signal according to the phase control signal during the ON period. The setting unit sets, for a Cartesian loop, a first loop gain when the switch is OFF, and a second loop gain higher than the first loop gain when the switch is turned from OFF to ON.

Abstract: According to one embodiment, a wireless power transmitter wirelessly transmits power to a power receiving apparatus which includes a first resonance circuit and a load circuit. The first resonance circuit includes a power receiving coil and a first capacitor. The wireless power transmitter comprises a second resonance circuit that includes a power transmission coil and a second capacitor and transmits the signal generated by a power supply to the power receiving apparatus, a measuring unit that measures a signal reflection coefficient, and a controller. The controller detects a value of an oscillation frequency of the power supply making the signal reflection coefficient smaller than or equal to a threshold value, calculates an electromagnetic coupling coefficient between the power transmission coil and the power receiving coil, and controls one of the oscillation frequency and a capacitance value of the second capacitor based on the electromagnetic coupling coefficient.

Abstract: In one embodiment, a power reception device includes a load circuit, to which a first signal having a first power value is supplied from a first resonance circuit connected to a power reception coil, and a first transceiver which transmits the first power value to a power transmission device. The power transmission device includes a second resonance circuit including a plurality of inductors and capacitors to which a second signal having a second power value is input, a power transmission coil connected to the second resonance circuit, a second transceiver which receives the first power value from the first transceiver, and a first control circuit which calculates power transmission efficiency using the first power value and the second power value and adjusts at least one of inductance values of the inductors and/or at least one of capacitance values of the capacitors based on the power transmission efficiency.

Abstract: A power feeding device includes an oscillator to generate a high frequency signal, a resonance frequency determining unit configured to determine a resonance frequency to be used for a wireless power transmission, a resonance frequency controller configured to generate a resonance parameter, a resonant circuit to generate electromagnetic inductance, and a communicating unit configured to notify a resonance frequency to the power receiving device before starting a wireless power transmission. A power receiving device includes a communicating unit configured to receive information of a resonance frequency to be used for a wireless power transmission, a resonance frequency controller configured to generate a resonance parameter, a resonant circuit to generate power, a load circuit to operate by the power, a switch to open and close a connection between the resonant circuit and the load circuit, and a determining unit configured to control the switch.

Abstract: In one embodiment, a wireless transmission apparatus is disclosed. The apparatus includes a generator unit, an amplitude adjuster unit, a phase adjuster unit, and a setting unit. The generator unit generates an amplitude control signal that minimizes an amplitude difference and a phase control signal that minimizes a phase difference in a state in which a power is set during an OFF period of a switch. The amplitude adjuster unit adjusts an amplitude of a feedback RF signal according to the amplitude control signal during an ON period of the switch. The phase adjuster unit adjusts a phase of a local signal according to the phase control signal during the ON period. The setting unit sets, for a Cartesian loop, a first loop gain when the switch is OFF, and a second loop gain higher than the first loop gain when the switch is turned from OFF to ON.

Abstract: An amplifier includes: a substrate; first to fourth amplifying units arranged on the substrate and each having first and second terminals, and each amplifying first and second signals to generate first and second amplified signals; a first inductive line arranged on the substrate, connecting the first terminal of the first amplifying unit and the first terminal of the second amplifying unit, and having a linear portion and a bending portion; a second inductive line arranged on the substrate, connecting the second terminal of the second amplifying unit and the first terminal of the third amplifying unit, and having a linear portion and a bending portion; a third inductive line arranged on the substrate, connecting the second terminal of the third amplifying unit and the first terminal of the fourth amplifying unit, and having a linear portion and a bending portion; a fourth inductive line arranged on the substrate, connecting the second terminal of the fourth amplifying unit and the second terminal of the firs

Abstract: An amplifier includes: a substrate; first to fourth amplifying units arranged on the substrate and each having first and second terminals, and each amplifying first and second signals to generate first and second amplified signals; a first inductive line arranged on the substrate, connecting the first terminal of the first amplifying unit and the first terminal of the second amplifying unit, and having a linear portion and a bending portion; a second inductive line arranged on the substrate, connecting the second terminal of the second amplifying unit and the first terminal of the third amplifying unit, and having a linear portion and a bending portion; a third inductive line arranged on the substrate, connecting the second terminal of the third amplifying unit and the first terminal of the fourth amplifying unit, and having a linear portion and a bending portion; a fourth inductive line arranged on the substrate, connecting the second terminal of the fourth amplifying unit and the second terminal of the firs

Abstract: A wireless transmission device includes an adding/subtracting unit configured to subtract a second signal and a third signal from a first signal to generate the second signal; a modulating unit configured to modulate the second signal to generate a fourth signal; a demodulating unit configured to demodulate the fourth signal to generate the third signal; and a transmitting unit configured to transmit the fourth signal.

Abstract: A voltage control circuit is connected to a voltage source. The voltage control circuit changes voltages of n different values and outputs them to an output node of the voltage control circuit according to control signals. A first switch element is connected between the output node of the voltage control circuit and a reference voltage node, and a second switch element is connected between the output node of the voltage control circuit and an output node of the voltage source. The first switch element is controlled so as to be conductive when the voltage control circuit changes the voltage of the output node from a first voltage to a second voltage that is lower than the first voltage, and the second switch element is controlled so as to be conductive when the voltage control circuit changes the voltage of the output node from a second voltage to a first voltage.