A cheap, current-regulated Luxeon Star driver design

An example of that would be driving four white Star/O LEDs, the cumulative forward voltage is 4* 3.65V = 14.6V. Add 3V for the driver, and the minimum supply voltage is 17.6V. Also note that the LM317T is capable of accepting a supply voltage up to 35V, so this driver circuit could run up to eight Luxeon Stars in series.

If you shop around, the parts to build this should cost less than a dollar, but you can definitely build it for less than two. This design is superior to the use of a current-limiting resistor with a regulated voltage supply, since less power is dissipated in the resistor for most cases, and more importantly this can be used with a relatively poorly-regulated input voltage without harming the expensive Luxeon Star.

Luxeon Star/O
looking into the business end of a blue Star/O
Luxeon Star/O
and a red one

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