LED Efficiency

Discussion in 'General Electronics Chat' started by Sensacell, Jun 5, 2015.

  1. Sensacell

    Thread Starter Senior Member

    Jun 19, 2012
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    391
    Designing some high power LED devices with SMD RGB LEDs.
    These parts are very small (5 x 5 mm) yest dissipate large amounts of power.
    For current 0.6 A and the forward LED voltage, the part will draw about 5 electrical watts with R,G,B all on.

    From the thermal perspective, I usually assume that all the power goes to heat, a conservative approach.
    But... as these devices become more efficient, this assumption becomes inaccurate:

    The question is:

    How do I calculate how much actual power (watts) that actually radiates in the form of light?
    Total power input (VA)= radiated optical power + heat energy produced.
    The heat output will always be less than the total input power, but by how much?
     
  2. Bordodynov

    Well-Known Member

    May 20, 2015
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    I don't know the efficiency Xlamp.
    But usually (depending on color) 5% -40%.
    I think that, on average, 20 per cent.
     
  3. Sensacell

    Thread Starter Senior Member

    Jun 19, 2012
    1,486
    391
    Hmmm. I need some handle on how to get a real number for this?
     
  4. Sonoran Desert Tortoise

    Member

    Oct 30, 2014
    54
    54
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