Power delivery device and control method thereof

A power delivery device, comprising:

• an output voltage control circuit, configured to control an output voltage of the power delivery device, to selectively switch the output voltage at one of a plurality of voltage levels, and configured to detect an output current of the power delivery device;
• and
• a power factor correction circuit, configured to increase a power factor of the power delivery device;
• wherein the power factor correction circuit is uncontrolled by the output voltage control circuit in response to a first load state of the power delivery device, and is controlled by the output voltage control circuit in response to a second load state of the power delivery device.

A control method, comprising:

• controlling, by an output voltage control circuit, an output voltage of a power delivery device selectively at one of a plurality of voltage levels;
• detecting, by the output voltage control circuit, an output current of the power delivery device;
• increasing, by a power factor correction circuit, a power factor of the power delivery device;
• remaining the power factor correction circuit being uncontrolled by the output voltage control circuit in response to a first load state of the power delivery device;
• and
• controlling the power factor correction circuit by the output voltage control circuit in response to a second load state of the power delivery device.