Abstract: An auto-resonant driver for a transmitter inductor drives the inductor at an optimal frequency for maximum efficiency. The transmitter inductor is magnetically coupled, but not physically coupled, to a receiver inductor, and the current generated by the receiver inductor is used to power a load. The system may be used, for example, to remotely charge a battery (as part of the load) or provide power to motors or circuits. A feedback circuit is used to generate the resonant driving frequency. A detector in the transmit side wirelessly detects whether there is sufficient current being generated in the receiver side to achieve regulation by a voltage regulator powering the load. This point is achieved when the transmitter inductor peak voltage suddenly increases as the driving pulse width is ramped up. At that point, the pulse width is held constant for optimal efficiency.

Abstract: An auto-resonant driver for a transmitter inductor drives the inductor at an optimal frequency for maximum efficiency. The transmitter inductor is magnetically coupled, but not physically coupled, to a receiver inductor, and the current generated by the receiver inductor is used to power a load. The system may be used, for example, to remotely charge a battery (as part of the load) or provide power to motors or circuits. A feedback circuit is used to generate the resonant driving frequency. A detector in the transmit side wirelessly detects whether there is sufficient current being generated in the receiver side to achieve regulation by a voltage regulator powering the load. This point is achieved when the transmitter inductor peak voltage suddenly increases as the driving pulse width is ramped up. At that point, the pulse width is held constant for optimal efficiency.

Abstract: An auto-resonant driver for a transmitter inductor drives the inductor at an optimal frequency for maximum efficiency. The transmitter inductor is magnetically coupled, but not physically coupled, to a receiver inductor, and the current generated by the receiver inductor is used to power a load. The system may be used, for example, to remotely charge a battery (as part of the load) or provide power to motors or circuits. A feedback circuit is used to generate the resonant driving frequency. A detector in the transmit side wirelessly detects whether there is sufficient current being generated in the receiver side to achieve regulation by a voltage regulator powering the load. This point is achieved when the transmitter inductor peak voltage suddenly increases as the driving pulse width is ramped up. At that point, the pulse width is held constant for optimal efficiency.

Abstract: A circuit and method for wirelessly coupling an electrical energy between an electrical energy source and at least one load is provided. The circuit comprises a primary unit and at least one secondary unit. The primary unit includes an input node for receiving an input voltage produced by the energy source; a transmitter circuit including a transmitter coil configured to generate an electromagnetic field; and a regulator. The regulator is configured to sense a current consumption of the primary unit, determine a gradient of the current consumption with respect to different input voltages, and determine an optimal input voltage based on the gradient. The at least one secondary unit comprises a receiver circuit and a load. The receiver unit includes a coil that wirelessly and inductively couples with the electromagnetic field of the primary unit to receive power therefrom. The receiver unit further includes a regulator circuit configured to provide a constant power to an output node.

Abstract: An auto-resonant driver for a transmitter inductor drives the inductor at an optimal frequency for maximum efficiency. The transmitter inductor is magnetically coupled, but not physically coupled, to a receiver inductor, and the current generated by the receiver inductor is used to power a load. The system may be used, for example, to remotely charge a battery (as part of the load) or provide power to motors or circuits. A feedback circuit is used to generate the resonant driving frequency. A detector in the transmit side wirelessly detects whether there is sufficient current being generated in the receiver side to achieve regulation by a voltage regulator powering the load. This point is achieved when the transmitter inductor peak voltage suddenly increases as the driving pulse width is ramped up. At that point, the pulse width is held constant for optimal efficiency.

Abstract: A circuit and method for wirelessly coupling an electrical energy between an electrical energy source and at least one load is provided. The circuit comprises a primary unit and at least one secondary unit. The primary unit includes an input node for receiving an input voltage produced by the energy source; a transmitter circuit including a transmitter coil configured to generate an electromagnetic field; and a regulator. The regulator is configured to sense a current consumption of the primary unit, determine a gradient of the current consumption with respect to different input voltages, and determine an optimal input voltage based on the gradient. The at least one secondary unit comprises a receiver circuit and a load. The receiver unit includes a coil that wirelessly and inductively couples with the electromagnetic field of the primary unit to receive power therefrom. The receiver unit further includes a regulator circuit configured to provide a constant power to an output node.