Wolfspeed
 | This article contains content that is written like an advertisement. (January 2009) |
Cree Inc. Nasdaq: CREE is a Durham, North Carolina based, American corporation which manufactures semiconductor materials and devices.
CREE generated $0.37 continuing earnings per share in 2008, and currently enjoys one of the highest trading multiples (highest P/E) on the Nasdaq stock exchange. It was formed in 1987 by researchers from North Carolina State University. Materials products include silicon, silicon carbide (SiC) and gallium nitride. Device products include light-emitting diodes (LEDs) made from their materials for a variety of uses, as well as power supply chips, motor controllers and microwave radios. The wide band gap semiconductors are suitable for high voltage or high power or high temperature operation. SiC is used for high power electronics, largely due to having a very high thermal conductivity. Two directors of Cree are John Palmour and Chuck Swoboda.
Some operations are now located in Hong Kong. The company's silicon fabrication line in Sunnyvale, California is closed, and the company is now focusing on wide band-gap technologies.
The company produced a prototype White LED that can produce 161 lumens per watt while drawing 350 mA of current, nearly 10 times what an incandescent (normal) light bulb can produce. [1] As of March 2009, the most efficient white Cree LEDs commercially available, such as the XLamp XR-E R2, achieve 100 lumens per watt. Based on more than 20,000h of continuous testing, Cree estimates that XR-E LEDs will lose 30% of their brightness over a usage period of 50,000h (barring overheating).[2]
Cree's competitors include Nichia Corporation, Osram Opto Semiconductors, Philips Lumileds Lighting Company and GE Lighting (Vio). Cree is also facing increasing competition from low cost Taiwanese LED manufacturers such as Epistar and Everlight Electronics.
History
In 2005, Cree opened a subsidiary, Cree Asia-Pacific Ltd., at the Hong Kong Science Technology Park to serve as a center of product innovation in Asia and provide customer and technical support, particularly in the area of packaged LED lighting components. [1] [2]
In 2007, Cree acquired Cotco Luminant Device Ltd of Hong Kong for $200 million. [3] Cotco is a supplier of high brightness LEDs in China.
In 2009, as a market leader in LED lighting, Cree announced an agreement to purchase a 592,000 square foot facility in Huizhou, Guangdong Province, China. The facility will be Cree’s first chip production facility outside of North America and is targeted to also house future components manufacturing expansion.[4]
Hi-Power LEDs
The Cree XLamp XP-E is a white LED mounted on a 3.5 by 3.5 mm base with a maximum drive current of 700 mA and a wide viewing angle of 115 degrees. It is available in Cool White (87.4 - 114 lumens at 350 mA), Neutral White (80.6 - 100 lumens), and Warm White (67.2 - 87.4 lumens). The typical forward voltage drop is 3.2-3.4 volts. [5]
All XLamp LED production units are sorted into a number of coded bins, based on color and brightness. Due to the power level and heat generated, adequate cooling is key to good usage of these parts. [6]
The XLamp XR-E is a white, blue or green LED mounted on a 7 by 9 mm base with a maximum drive current of 700-1000 mA and a viewing angle of 90-100 degrees, rated for 50,000 hours. It is available in Cool White (80.6 - 107 lumens at 350 mA), Neutral White (62.0 - 93.9 lumens), and Warm White (56.8 - 80.6 lumens); Royal Blue (300 - 425 mW), Blue (23.5 - 30.6 lumens) and Green (67.2 lumens). The typical forward voltage drop is 3.3-3.7 volts. [7] [8]
Newer addition are MC-E which are basically 4 XR-Es (individually addressable) in one package, able to produce up to 370-430 lm together when driven at 4x350 mA. [9]
The company has received a contract to provide energy efficient LED lighting to Walmart for new stores and renovations in November 2009.[10]
References
- ^ http://www.photonics.com/Content/ReadArticle.aspx?ArticleID=23682
- ^ http://www.cree.com/press/press_detail.asp?i=1143571572109
- ^ http://www.eetasia.com/ART_8800456466_480200_NT_fc1ab270
- ^ http://finance.yahoo.com/news/Cree-Signs-Agreement-for-bw-1288136645.html?x=0&.v=1
- ^ http://www.cree.com/Products/pdf/XLampXP-E.pdf Cree XLamp XP-E LEDs Data Sheet
- ^ http://www.cree.com/Products/pdf/XLampXP_B&L.pdf Cree XLamp XP-E and XP-C LED Binning and Labeling
- ^ http://www.cree.com/products/pdf/XLamp7090XR-E.pdf Cree XLamp XR-E LED Data Sheet
- ^ http://www.cree.com/Products/pdf/XLamp7090XR-E_B&L.pdf Cree XLamp XR-E and XR-C LED Binning and Labeling
- ^ http://www.cree.com/products/pdf/XLamp%20High%20Power.pdf Cree XLamp high-power LEDs compared
- ^ http://www.cleantechnology-business-review.com/news/cree_to_provide_cree_lrp38_led_light_bulbs_to_walmart_091104
External links
- Cree web site.
- CandlePower Forums - List of flashlights using the Cree XR-E Listing of current Flash Light Products utilizing the Cree LED.