Gathering information about Vf distribution Q5 and R2

[LightForce]

Hi,

I have an idea how to solve one of the problem of beginning modders.
We know that dealing with lack of voltage binning is a big minor side of Cree-enthusiasm. The problem is more difficult becouse I cannot find any precise information about Vf of the newer bins. "Higher than P4" - This not satisfy me and many of us. So I have a kind request and clever idea as well. Everyone who own Cree XR-E Q5 and especially R2 bins and who have capacity of measuring Vf at 1A accurately, please do follow:

Measure Vf of the cold LED, when it's heatsinked and when LED current is constant and about 1000mA (there can be a few percent error of course)

Type your results into the column. One column is the Q5, another - R2 bin.
We can also extend it to the R3 and more in the future.

If you have this information, please write the date of production/purchase next to it!


My LEDs:

Q5#1 3,56V (11.12.2007)
Q5#2 3,58V *
Q5#3 3,60V *

R2#1 didn't bought so far

Thanks in advance!

Cheers,
Damian

[znomit]

Perhaps the source would be useful too...

R2 Cutter Dec 07 3.57v (average over 3)

[Gryloc]

My friend got two Q5 emitters from a seller on the CPF Marketplace in Mid September of 2007. They were WG bin (color). For more information, contact adirondackdestroyer.

I hope that you do not mind if I include the Vf at other common currents.

          Q5 #1    Q5 #2
 350mA    3.48V    3.38V
 700mA    3.78V    3.67V
1000mA    3.94V    3.87V

Can I suggest that we start to unofficially "bin" the Vf of our XR-E emitters by some universal standard? We can use Lumileds' binning structure of the older Luxeon emitters, or maybe the structure of the newer Rebel and TFFC K2. Almost everyone on the CPF (if you grew up with the Luxeons) should be slightly familiar with the traditional binning structure. I do not know which current level we should bin the Q5s at, though. 350mA, 700mA, or 1000mA? The luminous flux of the XR-E has always been binned at 350mA, but knowing the Vf of the XR-E at 1000mA is just as useful for modders.

So, if you would bin my two Q5 LEDs above by the traditional structure:
Bin at 350mA:
Q5 #1 - J bin
Q5 #2 - J bin

Bin at 700mA:
Q5 #1 - L bin
Q5 #2 - K bin

Bin at 1000mA:
Q5 #1 - L bin
Q5 #2 - L bin

What do you think? I do not want to complicate things any further, or take over your thread. You are on to something. I, too am tired of guessing on the Vf of the XR-E. I think that the knowing the Vf is just as important as knowing the brightness and color!

-Tony

[EntropyQ3]

My friend got two Q5 emitters from a seller on the CPF Marketplace in Mid September of 2007. They were WG bin (color). For more information, contact adirondackdestroyer.

I hope that you do not mind if I include the Vf at other common currents.

          Q5 #1    Q5 #2
 350mA    3.48V    3.38V
 700mA    3.78V    3.67V
1000mA    3.94V    3.87V

Can I suggest that we start to unofficially "bin" the Vf of our XR-E emitters by some universal standard? We can use Lumileds' binning structure of the older Luxeon emitters, or maybe the structure of the newer Rebel and TFFC K2. Almost everyone on the CPF (if you grew up with the Luxeons) should be slightly familiar with the traditional binning structure. I do not know which current level we should bin the Q5s at, though. 350mA, 700mA, or 1000mA? The luminous flux of the XR-E has always been binned at 350mA, but knowing the Vf of the XR-E at 1000mA is just as useful for modders.

So, if you would bin my two Q5 LEDs above by the traditional structure:
Bin at 350mA:
Q5 #1 - J bin
Q5 #2 - J bin

Bin at 700mA:
Q5 #1 - L bin
Q5 #2 - K bin

Bin at 1000mA:
Q5 #1 - L bin
Q5 #2 - L bin

What do you think? I do not want to complicate things any further, or take over your thread. You are on to something. I, too am tired of guessing on the Vf of the XR-E. I think that the knowing the Vf is just as important as knowing the brightness and color!

-Tony

I'd vote against any such arbitrary binning scheme.
Just post the numbers. As long as the amount of data is in the low hundreds, you can still get a good overview just by looking, plus you can use the numbers for whatever statistical analysis makes sense to your application.

350mA, 700mA and 1000mA makes sense since the XR-Es, Rebels, and SSC P4s are binned at 350mA in the first place, and many applications aren't aiming at 1000mA use.