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XRCWHT-L1-0000-00501 Datasheet, PDF (12/16 Pages) Cree, Inc – XLamp XR-C LEDs
XLamp xr-c leds
Notes
Lumen Maintenance Projections
Cree now uses standardized IES LM-80-08 and TM-21-11 methods for collecting long-term data and extrapolating LED
lumen maintenance. For information on the specific LM-80 data sets available for this LED, refer to the public LM-80
results document at www.cree.com/xlamp_app_notes/LM80_results.
Please read the XLamp Long-Term Lumen Maintenance application note at www.cree.com/xlamp_app_notes/lumen_
maintenance for more details on Cree’s lumen maintenance testing and forecasting. Please read the XLamp Thermal
Management application note at www.cree.com/xlamp_app_notes/thermal_management for details on how thermal
design, ambient temperature, and drive current affect the LED junction temperature.
Moisture Sensitivity
XLamp LEDs are shipped in sealed, moisture-barrier bags
(MBB) designed for long shelf life. If XLamp LEDs are exposed
Temp.
Maximum Percent Relative Humidity
30% 40% 50% 60% 70% 80% 90%
to moist environments after opening the MBB packaging but 30 ºC
9
5
4
3
1
1
1
before soldering, damage to the LED may occur during the 25 ºC 12
7
5
4
2
1
1
soldering operation. The following derating table defines the 20 ºC
17
9
7
6
2
2
1
maximum exposure time (in days) for an XLamp LED in the
listed humidity and temperature conditions. LEDs with exposure time longer than the time specified below must be
baked according to the baking conditions listed below.
Cree recommends keeping XLamp LEDs in their sealed moisture-barrier packaging until immediately prior to use. Cree
also recommends returning any unused LEDs to the resealable moisture-barrier bag and closing the bag immediately
after use.
Baking Conditions
It is not necessary to bake all XLamp LEDs. Only the LEDs that meet all of the following criteria must be baked:
• LEDs that have been removed from the original MBB packaging.
• LEDs that have been exposed to a humid environment longer than listed in the Moisture Sensitivity section above.
• LEDs that have not been soldered.
LEDs should be baked at 80 ºC for 24 hours. LEDs may be baked on the original reels. Remove LEDs from MBB packaging
before baking. Do not bake parts at temperatures higher than 80 ºC. This baking operation resets the exposure time as
defined in the Moisture Sensitivity section above.
Storage Conditions
XLamp LEDs that have been removed from original MBB packaging but not soldered yet should be stored in a room or
cabinet that will maintain an atmosphere of 25 ± 5 ºC and no greater than 10% RH (relative humidity). For LEDs stored
in these conditions, storage time does not add to exposure time as defined in the Moisture Sensitivity section above.
Copyright © 2007-2013 Cree, Inc. All rights reserved. The information in this document is subject to change without notice. Cree®, the Cree logo and XLamp® are registered
trademarks of Cree, Inc.
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