Power Supply that will run off of 6or12 volts and output 3.5V with a constant current of 8.1A? It will power a ~22W LED.
If my calculations are correct, it is a 22W LED.
I need to power this LED from a 6V or 12V sealed-lead-acid battery. 6V is preferable but I can fit 12V in a dolphin style torch too. :)
I need to create this device, but not pay $60 for it: