Tighter binning yields more consistent HB LEDs for indoor apps

Vendors of HB LEDs (high-brightness light-emitting-diodes) make white HB LEDs by dosing a blue LED with a blob of phosphor that emits white light when blue light illuminates it. If cost were no object, a manufacturing process could precisely control the LED chip/phosphor combination to get a consistent white-light color temperature, but that level of control is prohibitively expensive. However, HB-LED vendors do provide LEDs that fall within certain color ranges, or bins, in a binning process.

If your end fixture uses multiple LEDs, a common design technique for outdoor lights such as streetlights, the lighting will be consistent as the LEDs’ color temperature averages out. However, some indoor applications lack the space to allow for multiple LEDs. Applications such as track lighting, spotlights, and can lights may use one HB LED, and the variation in light color temperature can be visible—as well as irritating.

Aiming at such applications, Cree recently announced EasyWhite bins in 3500, 3000, and 2700K color temperatures that are 75% smaller than standard color regions. Cree then uses EasyWhite LED chips in its multichip XLamp MC-E LEDs to obtain a more consistent white color temperature in a single LED package, which can serve as a replacement for 20 to 35W halogen light bulbs in indoor applications such as accent, track, and pendant lighting. The XLamp MC-EEasyWhite LED, at 3000K CCT (correlated color temperature), can produce as many as 560 lumens at 700 mA. EasyWhite LEDs cost about 15% more than Cree’s standard-bin LEDs.

Cree
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Cree’s EasyWhite bins come in 3500, 3000, and 2700K color temperatures and are 75 percent smaller than the ANSI C78.377-standard color regions.