In message
<of55b18620.c618ea44-on88257b21.00585dd6-88257b21.0059d...@selinc.com>,
dated Fri, 1 Mar 2013, [email protected] writes:
John is right. You want to feed LEDs a constant current, and let them
drop whatever voltage they need. If I am not mistaken, LEDs have a
negative voltage temperature coefficient. With this being the case,
feeding a constant voltage will cause the current to increase as the
diodes warm up. The additional current will cause more heating. This
can lead to a "runaway" situation.
I should have mentioned 'bad experience'. The runaway occurred only
after everything appeared stable and was very sudden - too sudden to
allow switch-off.
Dead LEDs for sale cheap on ebay!!!!
--
OOO - Own Opinions Only. See www.jmwa.demon.co.uk
SHOCK HORROR! Dinosaur-like DNA found in chicken and turkey meals
John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK
-
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