Patent ID: 8502474

Claim:
A single stage, primary side, Power Factor Correction (PFC) driver circuit, the circuit comprising: a rectifier circuit configured to rectify an alternating input voltage; an inductor coupled to the rectifier circuit; a diode coupled to the inductor and an output load; a switch coupled to the inductor; a switch control circuit coupled to the switch and configured for: generating a first signal for commanding the switch to allow the inductor to transfer energy provided by the rectified input voltage to the output load, the first signal having a first frequency with a duty cycle in proportion to an amplitude of the rectified input voltage; generating a second signal for commanding the switch, the second signal having a second frequency that is higher than the first frequency; and commanding the switch with the second signal based on the first signal, the commanding causing a substantial constant pulse current to be provided to the output load, resulting in an average input current being proportional to the amplitude of the rectified input voltage while the pulse current is substantially constant when provided to the output load.