Efficient Wireless Power Transfer Control

A wireless power transfer system comprising:

• a wireless power transmitter including:
• an inverter having an input configured to receive an input DC voltage and an output configured to provide an output AC voltage as a plurality of bursts;
• a transmit coil coupled to an output of the inverter to receive the plurality of bursts;
• and
• a wireless power receiver including:
• a receiver coil configured to magnetically couple to the transmit coil such that the plurality of bursts induce a corresponding AC voltage across the receiver coil;
• a rectifier having an input coupled to the receiver coil to receive the corresponding AC voltage from the receiver coil and an output configured to deliver a DC output voltage to a load;
• wherein the wireless power receiver further comprises burst request pulse generation circuitry configured to operate the rectifier so as to deliver a burst request pulse to the wireless power transmitter via magnetic coupling between the receiver coil and the transmit coil;
• and
• wherein the wireless power transmitter further comprises inverter control circuitry configured to sense the burst request pulse and, in accordance with sensing the burst request pulse, trigger the inverter to deliver an AC voltage burst.