Smaller, brighter LEDs can significantly cut LED bulb cost

Smaller, brighter LEDs can significantly cut LED bulb cost

Using silicon-carbide technology, XLamp XB-D series LEDs lay claim to having the smallest footprint (2.5 x 2.5 mm) for a lighting-class LED. Despite the small size, the LED provides high output; it produces up to 107 lm/W in warm white (3,000K) at 350 mA and a realistic operating junction temperature of 85°C, basically doubling the lumen-per dollar figure for LEDs, according to the manufacturer. The LEDs performance is such that designers of, say, retrofit bulbs can use fewer LEDs — as well as fewer optical elements and simpler electronics — in less space to deliver the same output as before at a lower cost, or use the same number of LEDs to boost bulb brightness.

The use of a silicon-carbide substrate (SiC) to grow gallium-nitride (GaN) LEDs provides a better lattice match between the two materials than when a silicon-on-saphire process is used, resulting in the production of more photons per unit area, or more light in less space, as well as higher efficacy. With better lattice match their are fewer defects, and hence greater production efficiency and higher reliability.

The LEDs are also compatible with most existing XP family secondary optics, which can speed the optical design process and save cost when using the new LEDs in existing XP family-based designs. In cool white (6,000K), the LEDs can deliver up to 139 lm/W at 350 mA and 85°C. (Samples, free; commodity pricing competitive with existing LEDs — samples available now, production quantities with standard lead times.)

By Richard Comerford

Cree , Durham , NC
Information 800-533-2583
http://www.cree.com/pct