LED DIM TO WARM CONTROLLER FOR LEDS

摘要

A control circuit is provided for a light emitting diode (LED) lighting system that achieves a dim-to-warm effect. The control circuit includes an LED controller, a clamp circuit coupled to the set of warm correlated-color-temperature ("CCT") LEDs, a switch coupled to the set of cool LEDs, and a feedback circuit coupled to the clamp and switch. The LED controller controls the clamp circuit to clamp the current through the set of warm LEDs based on the input current, switches on the set of cool LEDs in response to an input current greater than the first threshold level, and inputs lower than the first threshold level It is configured to control the switch to switch off the set of cool LEDs in response to the current. Feedback circuit It is configured to switch from a set of warm LEDs to a set of cool LEDs.