From: firstname.lastname@example.org (Bob Wilson)
Subject: Re: luxeon star leds
Date: Wed, 27 Nov 2002 05:00:02 -0000
Organization: Your Organization
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References: <3DDD9A57.58900EFB@RobertsResearchInc.com> <email@example.com> <3DDDB646.96D0D9D2@RobertsResearchInc.com> <3DDE7264.CD48F4F8@RobertsResearchInc.com> <firstname.lastname@example.org> <3DDEB081.884EC92A@RobertsResearchInc.com> <3DE03D65.932BF9BF@RobertsResearchInc.com> <3DE15871.EF8FF9EA@RobertsResearchInc.com> <3DE224D3.81EFBA3C@RobertsResearchInc.com>
In article ,
>In article ,
>email@example.com talked about...
>> Ooops, I missed that. But a luxeon without a heatsink would seem to be a
>> complete waste of an expensive LED. Without a heatsink, it is not
>> to push it to anywhere near its intended power level, May as well just
>> ordinary LEDs.
>The Luxeon has a _built-in_ heatsink. Somewhere I read that it stabilizes
>at 60 deg without any external HS.
That is completely incorrect. There are versions of the Luxeon LEDs that
come mounted to a metal core PCB. This is NOT a heat sink, in fact Lumileds
strongly warns in its literature (which is posted on their Luxeon website
for all to see) against operating the LEDs at full power for more than a few
moments, unless the heat spreader it is mounted to, is itself mounted to a
If you run a Luxeon LED (either the single LED, or the 12-LED Luxeon Line)
at full power, with only the heat spreader attached, the LED(s) will be
damaged by overheating in a few minutes. In fact, this is pretty obvious,
looking at the size of the heat spreader. Taking the single Luxeon with the
attached ~1" square metal core PCB attached to it, as an example, it is
obvious by inspection that this will not stabilize at only 60C, when you are
pumping a Watt into it.