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Thread: tech article - LED droop

  1. #1
    Flashaholic jerry i h's Avatar
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    Default tech article - LED droop

    http://spectrum.ieee.org/semiconductors/optoelectronics/the-leds-dark-secret/0
    http://www.scribd.com/doc/21615915/IEEE-Spectrum-Magazine-August-2009

    The droop in the article is not about the sag in lumens from a poorly heat-sinked Lux. CFL has efficiency of 100 lm/watt, LED is 250, but only at low power levels. Crank up the power, and the efficiency droops to only 100. The article reviews current research into this. They say that LED should be capable of 300. So, a 7 watt LED at 300 lm/watt will give the same light as a 100 watt incan, as opposed to the 23 watts required by CFL. I found the article to be quite interesting.
    Last edited by jerry i h; 12-01-2009 at 07:29 PM. Reason: fix it

  2. #2
    Thread Killer Illum's Avatar
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    Default Re: tech article - LED droop

    led efficiency has always been the highest in low current applications, why do many expect that efficiency value to apply at a higher current?

    If this was taking place as the light in your fridge maybe...but not in a Tj = 25C setting

  3. #3

    Default Re: tech article - LED droop

    Pretty sure this was already posted. I will have to go find it.

  4. #4
    Thread Killer Illum's Avatar
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    Default Re: tech article - LED droop

    or wait for Marduke, he is usually quite punctual

  5. #5
    Flashaholic jerry i h's Avatar
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    Default Re: tech article - LED droop

    Quote Originally Posted by saabluster View Post
    Pretty sure this was already posted. I will have to go find it.
    Yup:
    http://www.candlepowerforums.com/vb/...d.php?t=239096

    Late to the party again.
    Still, it is an interesting article. Too bad it won't happen anytime soon.

  6. #6

    Default Re: tech article - LED droop

    Quote Originally Posted by jerry i h View Post
    Yup:
    http://www.candlepowerforums.com/vb/...d.php?t=239096

    Late to the party again.
    Still, it is an interesting article. Too bad it won't happen anytime soon.
    Ah yes. Thats the one. Thanks for hunting it down.

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