Thread: Power LEDs
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Old June 3rd 08, 12:36 AM posted to rec.aviation.homebuilt
Morgans[_2_]
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Default Power LEDs


"RST Engineering" wrote in message
m...
It's really pretty easy. One version of the device has the LED bonded to
a PC board and through the PC board to an aluminum puck about a quarter
inch in diameter which (and this is the trick) is electrically INSULATED
from the diode. Since you generally are going to mount this sucker on the
last rib, or another hunk of aluminum out in the wingtip, all you do is
bolt the diode/pc board/puck assembly to the aluminum with a very thin
layer of thermal grease between the puck and the aluminum. I used a
representative scrap of aluminum about 30 square inches and the diode rise
over ambient was about 20°C. The allowable rise is well over 90C, so I
think I just about sunk it well enough. This was for two 5-watt diodes on
the same sink.


Cool! Well, cool enough, anyway! g

I figured there must be a requirement to have it bonded to some external
heat sink, or something that will help get rid of the heat. In a wood
airplane, it would require a bit of added metal, I suppose.

Thanks.
--
Jim in NC