A power delivery device, comprising: a power conversion circuit comprising a primary side and a secondary side, wherein the power conversion circuit is configured to receive an input voltage and convert the input voltage to an output voltage; and a power factor correction circuit, electrically coupled to the primary side and configured to increase a power factor of the power delivery device; wherein the power delivery device further comprises: an output voltage control circuit, electrically coupled to the secondary side and configured to control a voltage level of the output voltage and detect an output current of the power delivery device; a driving circuit, electrically coupled to the power factor correction circuit; and an isolating circuit, electrically coupled between the output voltage control circuit and the driving circuit, wherein when the voltage level of the output voltage is lower than a predetermined level and the output current is larger than a predetermined current value, the output voltage control circuit is configured to output a control signal to activate the isolating circuit, so that the isolating circuit drives the driving circuit to output a driving signal to deactivate the power factor correction circuit, wherein when the voltage level of the output voltage is lower than the predetermined level and the output current is smaller than the predetermined current value, the output voltage control circuit is configured not to activate the isolating circuit, such that the driving circuit is not driven by the isolating circuit to output a driving signal to deactivate the power factor correction circuit, wherein when the voltage level of the output voltage is larger than the predetermined level, the output voltage control circuit is configured not to activate the isolating circuit, such that the driving circuit is not driven by the isolating circuit to output a driving signal to deactivate the power factor correction circuit. a power conversion circuit comprising a primary side and a secondary side, wherein the power conversion circuit is configured to receive an input voltage and convert the input voltage to an output voltage; and a power factor correction circuit, electrically coupled to the primary side and configured to increase a power factor of the power delivery device; wherein the power delivery device further comprises: an output voltage control circuit, electrically coupled to the secondary side and configured to control a voltage level of the output voltage and detect an output current of the power delivery device; a driving circuit, electrically coupled to the power factor correction circuit; and an isolating circuit, electrically coupled between the output voltage control circuit and the driving circuit, an output voltage control circuit, electrically coupled to the secondary side and configured to control a voltage level of the output voltage and detect an output current of the power delivery device; a driving circuit, electrically coupled to the power factor correction circuit; and an isolating circuit, electrically coupled between the output voltage control circuit and the driving circuit, wherein when the voltage level of the output voltage is lower than a predetermined level and the output current is larger than a predetermined current value, the output voltage control circuit is configured to output a control signal to activate the isolating circuit, so that the isolating circuit drives the driving circuit to output a driving signal to deactivate the power factor correction circuit, wherein when the voltage level of the output voltage is lower than the predetermined level and the output current is smaller than the predetermined current value, the output voltage control circuit is configured not to activate the isolating circuit, such that the driving circuit is not driven by the isolating circuit to output a driving signal to deactivate the power factor correction circuit, wherein when the voltage level of the output voltage is larger than the predetermined level, the output voltage control circuit is configured not to activate the isolating circuit, such that the driving circuit is not driven by the isolating circuit to output a driving signal to deactivate the power factor correction circuit.