Greetings to Piclist community, i'm new to power-led design area. I have to design a led strip with 6 white power led. I chose Luxeon III Emitter White leds for my application. I have prepared the pcb and proper heatsink for my design. The strip will be sourced with 24V DC Meanwell smps. (this smps has max 10A drive capability) So i calculated required resistor value for driving the strip at 1A which is 24-6Vf = R (The datasheet of Lux III Emtter notes that it has 3.90 forward voltage at 1A) So i have chosen the Resistor value 0,75R / 5W. But when i conntected the serie to the power supply i only get 500mA and the value increased slowly to the 650mA and after that no increasing in current. I looked the luxeon datasheets and application notes over and over but still i havent found where is the problem? Do i need to design a specific smps with different topologies or else? (Datasheets and application notes can easily found on www.luxeon.com) -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist