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XLamp a19 RefeRence Design

trademarks of Cree, Inc. For product specifications, please see the data sheets available at www.cree.com. For warranty information, please contact Cree Sales at sales@cree.com.

figure 6: 4 Xp-e heW Leds in a 40-W-equivalent A19 lamp

In early 2011, cree built a cXa20011-based a19 bulb. In fact, in analyzing some a19 replacement lamps on the market,

we found one with a device driver that closely matched the CXA2011 voltage and current requirements, and as a first

pass replaced the LED array with a CXA2011. Results from this first experiment were somewhat disappointing. At

steady-state, the bulb produced 750 lumens and consumed 12.8 watts with a system efficacy of 58 Lm/W. Although

this level of performance is energy Star conformant, it was not in good correspondence with the pcT analysis shown in

Figure 5. We believe refinements to the heat sink assembly and a more recent driver circuit could deliver a substantial

improvement in performance.

figure 7: A19 bulb with a CXA2011 Led

Figure 6

Figure 7