Power factor correction controller with switch node feedback

A power factor correction (PFC) controller to control power factor correction and regulate output voltage at an output node of a switching power converter, the PFC controller comprising:

• an input to receive a feedback signal from the switching power converter;
• and
• wherein the PFC controller is configured to:
• determine a line input voltage and an output voltage of the switching power converter from the feedback signal, wherein during operation of the PFC controller the feedback signal is distinct from a signal on the output node of the switching power converter for a cycle of an input voltage signal supplied to the switching power converter;
• and
• provide a control signal to the switching power converter to control power factor correction and regulate output voltage of the switching power converter in response to the determined line input voltage and the determined output voltage of the switching power converter.

A method of controlling power factor correction of a switching power converter, wherein the switching power converter receives a periodic input signal and the switching power converter includes an inductor coupled to an input node and a switch node, a switch coupled to the switch node, and an output node coupled to a capacitor, the method comprising:

• receiving a feedback signal from the switch node, wherein the feedback signal from the switch node is distinct from a signal on the output node for a cycle of the input signal;
• determining from the feedback signal at least one of (i) the line input voltage and (ii) an output voltage of the switching power converter;
• determining at least one of (i) the line input voltage and (ii) the output voltage of the switching power converter;
• and
• providing a control signal to the switch to control power factor correction of the switching power converter in response to the determined line input voltage and the determined output voltage of the switching power converter.

An apparatus to control power factor correction of a switching power converter, wherein the switching power converter receives a periodic input signal and the switching power converter includes an inductor coupled to an input node and a switch node, a switch coupled to the switch node, and an output node coupled to a capacitor, the apparatus comprising:

• means for receiving a feedback signal from the switch node, wherein the feedback signal from the switch node is distinct from a signal on the output node for a cycle of the input signal;
• means for determining from the feedback signal at least one of (i) the line input voltage and (ii) an output voltage of the switching power converter;
• means for determining at least one of (i) the line input voltage and (ii) the output voltage of the switching power converter;
• and
• means for providing a control signal to the switch to control power factor correction of the switching power converter in response to the determined line input voltage and the determined output voltage of the switching power converter.