On 12/22/2011 2:21 AM, RussellMc wrote:
> Chinese made LEDs are a very variable feat - agin, world class through=20
> utter junk. Most failures occurred when 6 LEDS operated in parallel=20
> with a single shared series resistor (very naughty) were fed with 6 x=20
> rated current notionally shared amongst 6 LEDS.

I went through the chinese LED nightmare last week. These were boards of=20
LED with 12 LED on each board and 6 LED in series  connected to a common=20
connection point on each board. The boards were supplied power by a=20
driver that monitored the current and voltage.  The nightmare began when=20
one LED failed in a shorted state,  .3 ohms measured across it, then=20
another failed in the same way.  I began to replace the failed LED and I=20
did that for 4 of them, then one failed on another board and before I=20
knew it there were more failing than working. They were spec'd at 25ma=20
and the driver fed them 22ma and they still failed. Guess those 100 LED=20
for $5 bargains aren't bargains after all.
Mark

--=20
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