Abstract: An example apparatus as discussed herein includes a controller. The controller receives control input indicating how to control operation of a motor. In accordance with the control input, the controller controls a corresponding flow of current through each of multiple windings of the motor. According to one implementation, the controller balances positive demagnetization and negative demagnetization of each of the multiple windings in a respective control cycle.

Abstract: A gate driver circuit includes at least one driver configured to generate a first gate control signal for a first power disconnect switch and a second gate control signal for a second power disconnect switch in parallel with the first power disconnect switch, and logic configured to implement a delayed turn on time for the second gate control signal compared to the first gate control signal such that the first power disconnect switch turns on before the second power disconnect switch when powering up a load coupled to the first and the second power disconnect switches. The gate driver circuit logic may also be configured to implement a delayed turn off time such that the first power disconnect switch turns off before the second power disconnect switch when powering down the load. Corresponding power conversion circuits, electronic systems, and methods of power disconnect switch control are also described.

Abstract: A wireless power transfer (WPT) system that efficiently transfers power to portable devices over a wide range of load conditions and power output demands. The WPT system of this disclosure includes a full bridge topology. Changing the number of devices or the position and orientation of a device on the transmitter charge area may change the impedance and/or the load on the power transmitting unit (PTU). The WPT system of this disclosure may detect load impedance and/or power requested from the PTU. When the load exceeds a threshold, the WPT system will activate a second half bridge to operate in full-bridge mode. Similarly, the WPT system may detect the power requested and received and when the power drops to a certain threshold of power transmitted the WPT may turn off the second leg and operate in half-bridge mode.

Abstract: Techniques to sense the direction of current through the power transistor of an inverter drive circuit and the position of the rotor for a brushless direct current (BLDC) motor. During the time demagnetizing current flows, the power transistor is turned ON, directing the demagnetizing current through the lower impedance transistor channel rather than through the body diode. Directing current to the transistor channel may reduce the diode losses in the power transistors, thereby reducing the overall power losses. In other examples, the low side as well as the high side power transistor may be turned on during the time the demagnetizing current flows through the given power transistor.

Abstract: Techniques to sense the direction of current through the power transistor of an inverter drive circuit and the position of the rotor for a brushless direct current (BLDC) motor. During the time demagnetizing current flows, the power transistor is turned ON, directing the demagnetizing current through the lower impedance transistor channel rather than through the body diode. Directing current to the transistor channel may reduce the diode losses in the power transistors, thereby reducing the overall power losses. In other examples, the low side as well as the high side power transistor may be turned on during the time the demagnetizing current flows through the given power transistor.

Abstract: A wireless power transfer (WPT) system that efficiently transfers power to portable devices over a wide range of load conditions and power output demands. The WPT system of this disclosure includes a full bridge topology. Changing the number of devices or the position and orientation of a device on the transmitter charge area may change the impedance and/or the load on the power transmitting unit (PTU). The WPT system of this disclosure may detect load impedance and/or power requested from the PTU. When the load exceeds a threshold, the WPT system will activate a second half bridge to operate in full-bridge mode. Similarly, the WPT system may detect the power requested and received and when the power drops to a certain threshold of power transmitted the WPT may turn off the second leg and operate in half-bridge mode.