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A comparison of amber led types

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  • A comparison of amber led types

    A member asked for a comparison of the Luxeon Rebel amber led vs Cree. In context, it was as it related to the Triton V3 led bulb. I thought this reply might be of later use to others to understand the differences between them.
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    Well, there is no perfect answer as the brightness depends on quite a few factors, binning and die temperature being probably the most influential.

    I will try and give an example. I will use the Cree XPE amber led, I think that is their best amber offering right now.
    I will use 350mA drive current as the example, because it is offered in the datasheet. And I will use the P2 bin, as it's readily available. So, assuming you could keep the die temperature at 25C (77F which is quite a challenge) you can expect an output of 67 lumens * 3 = 201 lumens total.
    The MAXIMUM recommended drive current for that LED is 500mA, and at that current you can expect an output of 94*3 = 282 lumens.

    The Luxeon Rebel PC I will use the 0080 bin since that's coincidently what I am selling.
    So again at a drive current of 350mA you can expect luminous flux of 80 lumens each, * 3 = 240 lumens. This assumes the die temperature of 25C (77F) same as the Cree XPE.
    Now if you were to drive this Luxeon LED at 500mA, as with the Cree, you should see an output of 109.6 * 3 = 329 lumens. A pretty significant increase over the XPE.
    But, the max drive current for the Rebel PC amber is 700mA, not 500. So at THAT drive current you can expect 140 * 3 = 420 lumens. Now that is really a significant increase.

    There is also a Luxeon Rebel amber led made up of AllnGaP, same as the Cree XPE but UNLIKE the PC amber.
    The LXML-PL01-0050 is an available bin. 350mA = 50 lumens. * 3 = 150 lumens (25C, 77F)
    500mA = 65 lumens. * 3 = 195 lumens.
    700mA = 84 lumens. * 3 = 252 lumens.

    Now, if you are still with me, take a moment to look at these graphs I lifted from the data sheet.

    The above is from the Cree XPE data sheet, this is a AllnGaP LED as is the Rebel LXML-PL01. You can clearly see that the Amber led is extraordinarily susceptible to heat, far more so than other leds even of the same makeup. At 60C (140F) the output drops to only about 50% of what it would be at 25C!

    This next graph shows the luminous flux vs junction temperature for the Luxeon PC amber, the LXM2-PL01 and also the LXML-PL01. The LXM2 is the phosphor converted amber, and it is made up of Indium Gallium Nitride (InGaN). This accounts for it's higher forward voltage, but is much more durable.

    As you can see there, the brown line is the PC Amber. At 60C (140F) it maintains 88 - 90% of it's original flux! This is what REALLY separates the PC amber from the Aluminum Indium Gallium Phosphide (AlInGaP) leds.
    You can also see the standard amber, the LXML-PL01 at 60C (140F) will output about 60% of it's flux compared to 77F. Not nearly as good as the PC amber, but a far cry better than the Cree XPE.
    Last edited by VegasF6; September 26th, 2015, 08:09 PM.

  • #2
    Very helpful info, thanks!

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