Abstract: An apparatus comprises a rectifier configured to convert an alternating current voltage into a direct current voltage, wherein the alternating current voltage is generated by a receiver coil configured to be magnetically coupled to a transmitter coil of a wireless power transfer system, a high efficiency power converter connected to the rectifier, the high efficiency power converter comprising a first stage and a second stage connected in cascade and a controller configured to detect a plurality of operating parameters and generate a control signal applied to a control loop of the first stage.

Abstract: An apparatus comprises a rectifier configured to convert an alternating current voltage into a direct current voltage and a high efficiency power converter comprising a first stage and a second stage connected in cascade, wherein the first stage configured to operate in various operating modes for charging a battery and the second stage configured to provide isolation between the first stage and the battery.

Abstract: An apparatus comprises a power converter connected between an input power source and a wireless power transfer system, wherein the power converter is configured to regulate a voltage applied to the wireless power transfer system when a load current of the wireless power transfer system is less than a first threshold and the power converter is configured to operate in an always-on mode when the load current of the wireless power transfer system is greater than the first threshold.

Abstract: An overcurrent protection apparatus (50) and method for switch-mode power supplies (10) immediately clamps the peak power supply current when a sensed current magnitude exceeds a threshold current magnitude, reduces the threshold current magnitude if the overcurrent condition persists, and automatically attempts a restart of the power supply (10) to normal operation.

Abstract: A switching regulator control circuit provided with a summer to add the error signal an error amplifier with a target signal. The output of the summer is provided to a comparator which receives its other input from a ramp signal. In one embodiment, the reference voltage is modifiable and the target signal is proportional to the modifiable reference voltage. In another embodiment, the switching regulator is controlled by current mode control and the target signal is proportional to the load current demanded by the switching regulator's load.

Abstract: A cardioprotective composition for protecting heart against oxidative stress and methods for using and preparing the same. More particularly, the cardioprotective composition of the invention comprises a mixture of pyruvate, antioxidant, and lipid(s) such as fatty acids. The cardioprotective composition could be used for the treatment of heart attack/failure, the treatment of ischemic cardiopathy, the conservation of heart before and during transplantation, and the treatment heart oxidative stress related conditions.

Abstract: An overcurrent protection apparatus (50) and method for switch-mode power supplies (10) immediately clamps the peak power supply current when a sensed current magnitude exceeds a threshold current magnitude, reduces the threshold current magnitude if the overcurrent condition persists, and automatically attempts a restart of the power supply (10) to normal operation.

Abstract: A self-cooling transcutaneous energy transfer system is provided for transmitting power to an implantable medical device, such as a defibrillator. The system includes a housing that is supported above the human body by a base so as to define a space between the housing and the body. A primary induction coil is disposed within the housing for transferring electromagnetic energy to the implantable medical device. A cooling fan is attached to the housing for providing forced convective heat transfer from the body. Various power and control circuitry are provided. The system can transfer away heat generated by eddy currents induced in the implantable device by the magnetic flux produced by the induction coil.

Abstract: A data communication system for control of transcutaneous energy transmission to an implantable medical device is disclosed having an implantable medical device with rechargeable batteries and a single coil that is employed both for energy transmission and data telemetry. Control circuitry in the implantable device senses battery voltage and current through the battery, encodes those values by use of a multiplexer, and transmits the sensed and encoded values through the coil to an external energy transmission device. The external device includes a coil that is electromagnetically coupled to the coil in the implantable device for receiving the encoded signals and for transmitting energy to the implantable device. The external device decodes the transmitted values and transmits those to a controller for controlling energy transmission.

Abstract: An improved transcutaneous energy transmission device is disclosed for charging rechargeable batteries in an implanted medical device and to minimize peak temperature rises in the implanted device. A current with a sinusoidal waveform is applied to a resonant circuit comprising a primary coil and a capacitor. Current is induced in a secondary coil attached to the implanted medical device. Two solid state switches are used to generate the sinusoidal waveform by alternately switching on and off input voltage to the resonant circuit. The present invention charges the batteries using a charging protocol that either reduces instantaneous charging current or duty cycle of a fixed charging current as the charge level in the battery increases. Peak temperature rises are less while delivering comparable electrical charge of the battery than for prior charging systems.

Abstract: An improved transcutaneous energy transmission device is disclosed for charging rechargeable batteries in an implanted medical device. A current with a sinusoidal waveform is applied to a resonant circuit comprising a primary coil and a capacitor. Current is induced in a secondary coil attached to the implanted medical device. Two solid state switches are used to generate the sinusoidal waveform by alternately switching on and off input voltage to the resonant circuit. The sinusoidal waveform reduces eddy current effects in the implanted device which detrimentally increases the temperature of the implanted device. The present invention charges the batteries using a charging protocol that reduces charging current as the charge level in the battery increases. The controller preferably is constructed as a pulse width modulation device with a variable duty cycle to control the current level applied to the primary coil.