Hi folks, what’s the best way to power a string of high power LEDs? I have 10 3W LEDs that have a Forward Voltage of 3.2-3.8V and Forward Current of 600-700mA. I’d like to solder them together in a parallel string and power them off of one supply. Can I do that with a Femtobuck? Do I need something bigger/more powerful?
If the Femtobuck can handle 30W of power (and you should derate that to choose a part that can handle, say, 35-40W just in case) then it would work. Be sure to have good heat dissipation pathways ready because those things will get quite hot- both the LEDs and the buck converter, depending on how efficient it is. Lower efficiency means more heat generated.