Abstract: A gate driver circuit for a synchronous rectifier (SR) of a wireless power receiver (WPR) system includes: a first RC filter that outputs a delayed turn-on signal for a first high-side SR switch based on a signal input to the filter that indicates a zero-crossing condition for a coil current of the WPR system in a first direction; a second RC filter that outputs a delayed turn-on signal for a second high-side SR switch based on a signal input to the filter that indicates a zero-crossing condition for the coil current in the opposite direction; a first digital delay-and-hold circuit electrically connected to the output of the first RC filter and that stabilizes the delayed turn-on signal output by the first filter; and a second digital delay-and-hold circuit electrically connected to the output of the second RC filter and that stabilizes the delayed turn-on signal output by the second filter.

Abstract: A method of foreign object detection by a wireless power delivery system is disclosed. A decaying coil voltage signal of a transmitting coil of the wireless power delivery system is detected. A first comparator is used to trigger a cycle count of the decaying coil voltage signal. When the first comparator triggers the cycle count, a second comparator is used to count a number of cycles of the decaying coil voltage signal. A quality factor (Q-factor) of the transmitting coil is determined based on the number of cycles of the decaying coil voltage signal, a reference signal of the first comparator, and a reference signal of the second comparator. Whether a foreign object is present is determined based on the Q-factor and a foreign object detection (FOD) threshold level.

Abstract: Disclosed are techniques for using a sense amplifier for the voltage path having an adjustable gain and a current amplifier for the current path having an adjustable sample-hold interval for demodulation of in-band ASK data in power transmitting devices of a wireless charging system. The sample-hold interval may be adjusted as a function of the error rate of the demodulated data and used to sample the modulated current when the adjustable gain of the voltage path is not able to track the modulated voltage. The adjustable sample-hold may function as a variable reference of a comparator used to compare the sampled current to generate the sensed current. A controller may flexibly adjust the gain, adjust the sample-hold interval, and/or select the sensed voltage or the sensed current path for further filtering, demodulation, decoding, and processing depending on the error rate under various loading, coupling scenarios, and phases of power transfer.

Abstract: Systems, methods, and devices are described to improve wireless charging devices. Systems include a power inverter configured to generate a power transfer signal based, at least in part, on a plurality of transmission parameters, a transmission element configured to wirelessly transmit the power transfer signal, and a controller configured to determine a power transfer mode used by the power inverter based, at least in part, on a plurality of operational parameters and a plurality of configuration parameters.

Abstract: Disclosed are techniques for using a sense amplifier for the voltage path having an adjustable gain and a current amplifier for the current path having an adjustable sample-hold interval for demodulation of in-band ASK data in power transmitting devices of a wireless charging system. The sample-hold interval may be adjusted as a function of the error rate of the demodulated data and used to sample the modulated current when the adjustable gain of the voltage path is not able to track the modulated voltage. The adjustable sample-hold may function as a variable reference of a comparator used to compare the sampled current to generate the sensed current. A controller may flexibly adjust the gain, adjust the sample-hold interval, and/or select the sensed voltage or the sensed current path for further filtering, demodulation, decoding, and processing depending on the error rate under various loading, coupling scenarios, and phases of power transfer.

Abstract: A gate driver circuit for a synchronous rectifier (SR) of a wireless power receiver (WPR) system includes: a first RC filter that outputs a delayed turn-on signal for a first high-side SR switch based on a signal input to the filter that indicates a zero-crossing condition for a coil current of the WPR system in a first direction; a second RC filter that outputs a delayed turn-on signal for a second high-side SR switch based on a signal input to the filter that indicates a zero-crossing condition for the coil current in the opposite direction; a first digital delay-and-hold circuit electrically connected to the output of the first RC filter and that stabilizes the delayed turn-on signal output by the first filter; and a second digital delay-and-hold circuit electrically connected to the output of the second RC filter and that stabilizes the delayed turn-on signal output by the second filter.

Abstract: A method of foreign object detection by a wireless power delivery system is disclosed. A decaying coil voltage signal of a transmitting coil of the wireless power delivery system is detected. A first comparator is used to trigger a cycle count of the decaying coil voltage signal. When the first comparator triggers the cycle count, a second comparator is used to count a number of cycles of the decaying coil voltage signal. A quality factor (Q-factor) of the transmitting coil is determined based on the number of cycles of the decaying coil voltage signal, a reference signal of the first comparator, and a reference signal of the second comparator. Whether a foreign object is present is determined based on the Q-factor and a foreign object detection (FOD) threshold level.

Abstract: Pseudo-digital light-emitting diode (LED) with secondary-side flyback control is described. In one embodiment, a Digital Addressable Lighting Interface (DALI) compatible driver includes a secondary-side controller coupled to a secondary winding of a transformer and coupled to a light-emitting element. The secondary-side controller includes a DALI-compatible interface to receive information. The secondary-side controller communicates a control signal with a primary-side controller via a galvanically-isolated link. The primary-side controller is coupled to a primary winding of the transformer. The DALI-compatible driver modifies a light output of the light-emitting element in response to the information.

Abstract: Pseudo-digital light-emitting diode (LED) with secondary-side flyback control is described. In one embodiment, a Digital Addressable Lighting Interface (DALI) compatible driver includes a secondary-side controller coupled to a secondary winding of a transformer and coupled to a light-emitting element. The secondary-side controller includes a DALI-compatible interface to receive information. The secondary-side controller communicates a control signal with a primary-side controller via a galvanically-isolated link. The primary-side controller is coupled to a primary winding of the transformer. The DALI-compatible driver modifies a light output of the light-emitting element in response to the information.

Abstract: A control system that facilitates energy efficient management of building automation systems is disclosed. The control system comprises a source circuit configured to generate a modulated DC control signal comprising data modulated on a DC source signal having a power associated therewith and a load circuit configured to receive the modulated DC control signal. In addition, the control system comprises a transmission circuit comprising a DC powerline, coupled between the load circuit and the source circuit, and configured to transfer the modulated DC control signal from the source circuit to the load circuit, thereby multiplexing both the power and the data transfer over the DC powerline. In some embodiments, a frequency of the modulated DC control signal comprises a first information associated with the data, and a pulse width of the modulated DC control signal comprises a second, different information associated with the data.

Abstract: A control system that facilitates energy efficient management of building automation systems is disclosed. The control system comprises a source circuit configured to generate a modulated DC control signal comprising data modulated on a DC source signal having a power associated therewith and a load circuit configured to receive the modulated DC control signal. In addition, the control system comprises a transmission circuit comprising a DC powerline, coupled between the load circuit and the source circuit, and configured to transfer the modulated DC control signal from the source circuit to the load circuit, thereby multiplexing both the power and the data transfer over the DC powerline. In some embodiments, a frequency of the modulated DC control signal comprises a first information associated with the data, and a pulse width of the modulated DC control signal comprises a second, different information associated with the data.