WS3440

WS3440 Product Description Constant Current Controller For Non-isolated Buck LED Driver Features � Inductor Current Critical Mode, No Need to Compensate the Inductance Variation � Source Driver Structure, Not Need the Auxiliary Winding for VCC � ±3% LED Current Accuracy � Up to 93% System Efficiency � LED Short Circuit Protection � Current Sense Resistor Short Circuit Protection � Over Temperature Protection � Programmable LED open protection Applications � LED Bulb � LED Candle light � LED Spot light � Decorative LED lighting General Description The WS3440 is a high precision constant current controller， designed for non-isolated buck LED driver. suitable for AC input voltage range (84V-264V) The WS3440 uses high precision current sense circuit and patent method for constant current control, to achieve high precision output current and excellent line regulation. The WS3440 operates in inductor current critical mode. The LED current is constant over wide range of inductance variation and the LED output voltage, so the load regulation is excellent. The WS3440 uses patent source driver architecture. The operation current is 200uA only, so the auxiliary winding is not needed. It can simplify the system design and reduce the system cost. The WS3440 offers rich protection functions, including LED open/short circuit protection, current sense resistor short circuit protection and over temperature protection. Typical Application Circuit AC 1 ROVP G ND 2 6 V C C G ATE 5 3 CS S...