Cree doubles lumen density in 9-mm COB LED family
Cree has announced the latest member of its chip-on-board (COB) LED array family with the CXA1520 delivering 2000–4000 lm from a 9-mm light emitting surface (LES). The company is targeting the new LED for replacement of high-output ceramic metal-halide (CMH) sources that are regularly used for directional accent lighting when halogen lamps can't deliver sufficient light levels.
Cree calls the new LED array a high-density product, referring to the fact that more die are packed into the 9-mm area, although the application is also a solid-state lighting (SSL) product that delivers high-density beams. Cree product marketing manager Paul Scheidt said that the CXA1520 is the only COB LED array on the market at 9 mm that can deliver the 40,000-cd center beam candle power (CBCP) required of a replacement lamp for PAR30 CMH sockets. He added that the new array offers double the lumen output of competitors' products and prior Cree products with the same LES.
"The CXA1520 LED array enables ConTech Lighting's newest LED fixtures to exceed the efficiency and life of our ceramic metal-halide fixture offerings while maintaining intensity and color quality," said Mark Groenke, vice president of engineering at ConTech Lighting. "The new CXA1520 LED array delivers an impressive amount of light from a very small source. I have not seen another integrated array that can match this level of lumen density."
Cree's Scheidt explained that before now, you could realize the CMH replacement using the 19-mm CXA2530 LEDs, albeit at a much higher power level and with less ability to control the beam. Cree built a reference design that demonstrates 40,000-cd levels in the center of a beam with the LED delivering only 2000 lm at 22W.
The addition of the CXA1520 gives directional retrofit lamp makers considerable scalability to use the same basic lamp design and serve a breadth of applications. Scheidt said a manufacturer could use the same optics to realize a 75W-halogen-equivalent lamp with the CXA1507, a 100W-halogen- or 20W-CMH-equivalent lamp with the CXA1512, or the new LED for the 39W-CMH-equivalent lamp.
Such a family would require higher-current drivers as the lumen package goes up, and perhaps an enhanced thermal design. But Scheidt said that the optics design is the most time consuming in a retrofit lamp project and that "nearly the exact same design supports a range of products."
At least one customer already likes the scalable angle of the family. "We have several CXA1507 and CXA1512 LED array designs and we're excited that the new CXA1520 LED array shares the same light-emitting size as the CXA1507 and CXA1512 LED arrays," said Tom Tang, chairman and CEO, Tons Lightology, Inc. "This allows us to address very high output applications without changing the optics."
The new LEDs are offered in 2700K to 5000K CCTs, with 70-, 80-, and 90-CRI options. Scheidt would not detail how Cree achieved the higher output levels beyond saying the new LED uses a die that hasn't been used previously in the arrays, the array is packed more tightly, and the product uses a new substrate material.