The company claims that this represents the industry's first demonstration of "lighting class" warm-white LEDs. Products are already being shipped to paying customers.
Most warm-white power LEDs are not qualified to operate above 350 mA, although there are a few exceptions. For more on this subject, see our recent article "Warm white LEDs ready for a leap forward in 2007."
"The LED industry has struggled to boost the brightness and efficiency of warm white LEDs, which have historically offered significantly lower performance than cool white LEDs," stated Norbert Hiller, Cree Lighting general manager and vice president.
"The new XLamp warm white LEDs hold a stable color point and offer lighting designers and architects the first lighting-class warm white LED light source for general illumination applications that have traditionally been lit with incandescent light sources."
The new devices show color point stability within a 4-step MacAdam ellipse when driven at 700 mA. Older-generation XLamp devices (and many competing devices) can only demonstrate this level of color point stability at 350 mA.
The new warm white is available in both the XLamp XR-E and XR-C power LED families. The devices are binned according to the proposed ANSI chromaticity standard for LEDs, which is itself based on specifications for compact fluorescent lamps. This allows lighting manufacturers to select LEDs the same way they select lamps today.
Cree's datasheet for the high-end XR-E family shows a typical luminous flux of 70 lm at 350 mA and 120 lm at 700 mA for a 3700K LED. The corresponding values are 65 lm (equivalent to 56 lm/W) and 110 lm (around 45 lm/W) at 2600K.
Cree representatives told LEDs Magazine that the new leap in performance demonstrated by the company's warm white products will now allow lighting manufacturers to start to address the "low-hanging fruit" among indoor lighting applications, paving the way for further penetration in the future.
