5

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.

Characteristic

Requirement

luminous intensity distribution

products shall have an even distribution of luminous intensity (candelas) within the 0° to

135° zone (vertically axially symmetrical).

luminous intensity at any angle within this zone shall not differ from the mean luminous

intensity for the entire 0° to 135° zone by more than 20%.

At least 5% of total flux (lumens) must be emitted in the 135°-180° zone.

Distribution shall be vertically symmetrical as measured in three vertical planes at 0°, 45°

and 90°.

Maximum lamp diameter

Not to exceed target lamp diameter as per ANSI C78.20-2003.

Maximum overall length (MOL)

Not to exceed MOL for target lamp as per ANSI C78.20-2003.

lumen maintenance

l70 > 25,000 hours

rapid-cycle stress test

cycle times must be 2 minutes on, 2 minutes off. lamp will be cycled once for every 2

hours of required minimum l70 life.

color angular uniformity

The variation of chromaticity shall be within 0.004 from the weighted average point on the

cIe 1976 (u’, v’) diagram.

table 3: energy star requirements for omnidirectional lamps

The performance system performance requirements for non-standard and omnidirectional lamps, as shown in Tables 3

and 4, are essentially the same. The latter has defined luminous intensity distribution and minimum light output, which

allow the lamps to be compared more readily to the incandescent lamps they replace.