Cree P3, P4, Q2 differences

[DonShock]

When answering a question on CPF earlier today, I got to taking a close look at the Cree LEDs is several of my modifications. And I think I figured out a way to tell the difference between the P3, P4, and Q2 bins based on looking at differences in the die inself. Before I continue to describe the differences, I need to mention that this assumes the LEDs I recieved from the various vendors were of the bins promised. The multiple Crees of a single order of each type shown were consistant in their appearances and the differences between types as noted. So I am fairly confidant that these features are representative of the different bins. But these are just my obsevations, so take them for what they are worth. Maybe somebody with access to more LEDs or from more verifiable sources can confirm this independantly.


On to the juicy info. Here are some thumbnails of my photos of the Cree dies on each different bin of LED. Click on them for a full resolution picture. This was as close as I could get with my digital camera, and some of the differences were more apparent using a 15x loupe. Especially the location of the small "sub-square". In the photos, it's all shades of yellow but you should be able to make it out if you look carefully at the pictures. Looking through a loupe by eye, it should be fairly easy to see.

Cree P3:
3 bond wires, "tab" on one end only, small "sub-square" at corner of end

Cree P4:
3 bond wires, "tab" on both ends, small "sub-square" at center of one end

Cree Q2:
4 bond wires, "tab" on both ends, small "sub-square" at center of one end


I hope this helps when you need to figure out the bin of an unknown Cree LED. If I get some other bins and can figure out some distinguishing characteristics, I'll add them to this thread.

 

[Lite_me]

This tells me my JetBeam C-LE v1.2 has a Cree Q2 in it! Nice! :thumbsup:

Edit: Well, it looks like that's no guarantee. :thumbsdow Darn.

 

[KWillets]

Also, is there a Vf difference? I see mentions here and there, but I went through the Cree binning document and found nothing.

 

[cmacclel]

I just checked some of the LED's I had on hand. All my Q2 bins had 4 bond wires. Some P3's had 4 bond wires and some P4's had 3 bond wires. Is this an offical way to tell or just guessing?

Mac

 

[DonShock]

.... Is this an offical way to tell or just guessing?

Mac

I don't have any inside official information, this is just me looking at looking at the different LEDs I have recieved and noting the differences.

......But these are just my obsevations, so take them for what they are worth. Maybe somebody with access to more LEDs or from more verifiable sources can confirm this independantly.....

I added this in because I know I have a limited sampling of LEDs in my possession. I don't know if my observations apply to all the Crees out there, but it's how the ones ones I have in my possession differ according to bin. And with one exception, every LED I have of the same bin has the same appearance. I know I could be completely out to lunch in my limited observations.

 

[StefanFS]

I have used four CREE Q2 WC for modding, they are brighter than my P4 so I don't think I was scammed. They all have 3 bond wires. I think that the thing with four wires is just a slight change in design and manufacturing.
Stefan