anonymous coward wrote:
Have you considered using a constant current regulator, instead of a
resistor? I believe there is an example circuit given in the LM337/317
datasheet showing how to build one using only the LM337 (normally used as
a voltage regulator) & one resistor.

It would need to be bolted to a heatsink, like the Luxeon Star LEDs, but
IIRC the LM337 and cousins also shut down if they overheat.

AC


Yes. I considered it. I opted for the simplicity of a single current
limiting resistor and the constant voltage regulator that is already
there. Number one rule of fault management. If it ain't there, there's
no way to break it. Regulators not only add an additional active
component with its list of failure modes, it also adds severl solder
connections and more heat, making it even more difficult to rig the
system into a 1/4" piece of plexiglass.


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