mudman cj
Flashlight Enthusiast
Not exactly - binning is typically done at a specified current. Rebels are now binned at a specified power level, which guarantees a certain Vf. It is quite possible to get an LED from other manufacturers binned for 100 lumens at 350mA that consumes well over 1 Watt. And since binning assumes a 25 degrees Centigrade die temperature, the actual lumens from the LED will be that much lower due to thermal derating.
For the sake of clarity I will provide an example.
A neutral white Q4 bin XP-E is rated to put out 100 lumens at 350 mA. A typical Vf for an XP-E is 3.2V, but could be as high as 3.9V (though anything over 3.6V is uncommon). This gives a range of 1.12 - 1.365 Watts.
A neutral white Rebel 100 binned to put out 100 lumens per watt will be at 1 Watt maximum.
Now, if we consider the effect of the extra heat on raising the die temperatures and therefore lowering the output (thermal derating), it is clear that the Rebel will put out more light than the XP-E at the same current.
For the sake of clarity I will provide an example.
A neutral white Q4 bin XP-E is rated to put out 100 lumens at 350 mA. A typical Vf for an XP-E is 3.2V, but could be as high as 3.9V (though anything over 3.6V is uncommon). This gives a range of 1.12 - 1.365 Watts.
A neutral white Rebel 100 binned to put out 100 lumens per watt will be at 1 Watt maximum.
Now, if we consider the effect of the extra heat on raising the die temperatures and therefore lowering the output (thermal derating), it is clear that the Rebel will put out more light than the XP-E at the same current.
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