Good to see, not that I was worried about it though. I don't know why people are so worried about the heatsinking of the Rebel. Something tells me that Lumileds knows a tad more about LEDs than most CPFers and I'm pretty sure they've done a tiny bit of research before releasing the Rebel in its current configuration...
I think you are giving the Lumiled morons way too much credit.
First they take the time to push the state of the art up to new highs in lumens/watt then package the Rebel in this CRAPPY little poorly designed asymmetric package.
The heat pad, that everyone is so worried about is not only TINY, it doesn't even cover the area that it could on the bottom of the package! Gee, that seems pretty stupid, doesn't it?
The electrical connection pads are also quite TINY considering the 700mA to 1A of current that you could be pushing through them. This is made worse by the fact that surface mount devices somtimes get placed a little off center, which would further reduce the contact area. Also, they are all the way over at the end of their cockeyed asymmetric package, with only these skinny little conductor tracks along the top of the package to connect to the die. At a time when others are adding additional bond wires to lower Vf, why increase the package resistance unnecessarily in this way? STUPID AGAIN!
I can't think of a single reason for cockeyed little asymetric package (other than the fact that it's cheap to produce), unless the Lumiled folks, aware that CREE, and Soeul will be hot on their heels with higher output chips, figured that they would get clever and come up with this tiny little package that can be 'clustered' (so even if you can't push any more lumens out of the poor little rebel chip, you can just buy three or four and jam them together in a kind of Lumiled Cluster-F...).
A square or only slightly rectangular package with about 20% more width than the current rebel's narrowest dimension, and with the emitter CENTERED and contacts at the ends would be at least as good thermally, and MUCH better for most LED flashlight applications, which use a SINGLE LED and where you have to fit the emitter up inside existing reflector designs.
For those who do need to 'cluster' the rebel chips, or who already have automated production set up for the current design, Lumiled should obviously continue to offer them, but with many IC's and other semiconductor devices already available in multiple package types, I look forward to seeing the Rebel LED die offered in a more intelligently designed package.
So, for the record; I have worked with the Rebels; Love the performance, HATE the packageing.
:thumbsup:. THANK YOU!
