Patent ID: 8957600
Filing Date: 2015-02-17
Classification: H05B

Abstract:
1. A light emitting diode (LED) driver for powering an LED load at a substantially constant current, comprising: a buck topology power factor correction (PFC) circuit, the buck PFC circuit having a PFC controller, the buck PFC circuit configured to draw an alternating current (AC) input current having a first total harmonic distortion (THD), the PFC controller configured to sense a rectified input voltage from a full-wave rectifier, the PFC circuit outputting a direct current (DC) voltage and a DC current; a downstream isolation and regulator circuit configured to receive the DC voltage and the DC current output by the buck PFC circuit and to provide the substantially constant current to the LED load; and a passive voltage squarer circuit configured to square the rectified input voltage sensed by the PFC controller, whereby squaring the rectified input voltage sensed by the PFC controller causes the input AC current drawn by the buck PFC circuit to have a second, improved THD.