NewBie
*Retired*
Production CREE XR-E Testing (SLOW lots of pictures!)
First off, CREE made a vast improvement in the Vf of their LEDs, and it holds quite well with increasing current. In fact, I know of no other power LED company producing LEDs with Vf's this low. Why does it matter? Power consumed is Current * Voltage. So, here is the first chart, compared with a Philips LumiLEDs Luxeon K2, their latest device:
Next, I measured the lumen output (I figure accuracy is +/-10%), vs. current:
This is also a vast improvement vs. any other LED I've tested to date, and pretty much, producing roughly 2x more light than other similar LEDs at the same current. Or looking at it another way, at the same light output, this part consumes about half the current, so your batteries will last 2x as long, and the LED will produce half the heat.
Due to the extra low Vf, and the outstanding amount of lumens comming out of the device at a given current, when you multiply these two together, the total power is often less than half, compared to most devices.
The extra high lumen output of this device, vs. power consumed, means it is more efficient, and more of you power leaves the device as light, instead of being converted to heat. Heat is the bane of LEDs and reduces both their expected lifetime and lumen output.
Yes, you can find the rare unobtainium bin of some whizbang Philips Luxeon, but they are rare, and still won't come close to matching the lumens vs. current of the CREE XR-E. CREE also makes some premium bins, this one tested here is just a run of the mill part.
For testing, the device was directly soldered to a 2" by 3" plate of 0.162" copper slab, and set on a table with no cooling air. Your results may be better, if you are more agressive in your heatsinking.
First off, CREE made a vast improvement in the Vf of their LEDs, and it holds quite well with increasing current. In fact, I know of no other power LED company producing LEDs with Vf's this low. Why does it matter? Power consumed is Current * Voltage. So, here is the first chart, compared with a Philips LumiLEDs Luxeon K2, their latest device:
Next, I measured the lumen output (I figure accuracy is +/-10%), vs. current:
This is also a vast improvement vs. any other LED I've tested to date, and pretty much, producing roughly 2x more light than other similar LEDs at the same current. Or looking at it another way, at the same light output, this part consumes about half the current, so your batteries will last 2x as long, and the LED will produce half the heat.
Due to the extra low Vf, and the outstanding amount of lumens comming out of the device at a given current, when you multiply these two together, the total power is often less than half, compared to most devices.
The extra high lumen output of this device, vs. power consumed, means it is more efficient, and more of you power leaves the device as light, instead of being converted to heat. Heat is the bane of LEDs and reduces both their expected lifetime and lumen output.
Yes, you can find the rare unobtainium bin of some whizbang Philips Luxeon, but they are rare, and still won't come close to matching the lumens vs. current of the CREE XR-E. CREE also makes some premium bins, this one tested here is just a run of the mill part.
For testing, the device was directly soldered to a 2" by 3" plate of 0.162" copper slab, and set on a table with no cooling air. Your results may be better, if you are more agressive in your heatsinking.
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