WIRELESS POWER TRANSMITTER, CONTROL CIRCUIT AND CONTROL METHOD THEREOF, AND CHARGER

摘要

A wireless power transmitter for transmitting a power signal to a wireless power receiver is disclosed. The transmitter includes a transmission antenna, an inverter circuit including a plurality of switches; and a control circuit configured to demodulate a control signal received by the transmission antenna from the transmitter and control the inverter circuit based on power control data included in the control signal. The control circuit is configured to select among a first, second and third mode. For example, in the first mode in which a first pair including first and second switches and a second pair including third and fourth switches are both complementarily switched at a duty ratio of 50%, and a phase difference of the first pair and the second pair is changed between a minimum value and a maximum value depending on a transmission power, and the inverter circuit performs a full-bridge operation.

主权项

1. A wireless power transmitter for transmitting a power signal to a wireless power receiver, comprising:
a transmission antenna including a transmission coil; an inverter circuit including a first switch installed between a power line and one end of the transmission antenna, a second switch installed between the power line and the other end of the transmission antenna, a third switch installed between the one end of the transmission antenna and a ground line, and a fourth switch installed between the other end of the transmission antenna and the ground line; and a control circuit configured to demodulate a control signal received by the transmission antenna from the wireless power transmitter and control the inverter circuit based on power control data included in the control signal, wherein the control circuit is configured to select: (i) a first mode in which a first pair including the first switch and the second switch are complementarily switched at a duty ratio of 50%, a second pair including the third switch and the fourth switch are complementarily switched at a duty ratio of 50%, a phase difference of the first pair and the second pair is changed between a minimum value and a maximum value depending on a transmission power, and the inverter circuit performs a full-bridge operation; (ii) a second mode in which the first pair are complementarily switched at a duty ratio of 50%, a switching frequency is changed depending on the transmission power, and the inverter circuit performs a half-bridge operation; and (iii) a third mode in which the first pair are complementarily switched at a duty ratio of 50%, the second pair are complementarily switched at a duty ratio of 50%, the phase difference of the first pair and the second pair is changed to the minimum value, the switching frequency is changed depending on the transmission power, and the inverter circuit performs a full-bridge operation.