LED thermal limits

vbsaltydog · 08/30/2015, 11:42 PM

I am building a thermal protection circuit for my DIY LED build. I was wondering what the recommended max continual heat is on LEDs, generally speaking of course.

I am using the 70w multichips from clay-boa (the lumia 5.2 chips). I currently have a temperature of ~105 degrees fahrenheit, roughly 1/4" above the multichip pad's surface when running the chips at 60% power.

Thanks

theatrus · 08/31/2015, 12:55 AM

Many LEDs are rated for operation at an 80-85C junction (die) temperature. This is of course nearly impossible to measure directly, so you back calculate based on thermal resistances.

Rough guessing, I wouldn't want the heat sink base above 50C.

vbsaltydog · 08/31/2015, 01:13 AM

That seems reasonable. Thanks.

08/30/2015, 11:42 PM	#1
vbsaltydog Registered Member Join Date: Oct 2007 Location: Melbourne Beach, FL. Posts: 603	LED thermal limits I am building a thermal protection circuit for my DIY LED build. I was wondering what the recommended max continual heat is on LEDs, generally speaking of course. I am using the 70w multichips from clay-boa (the lumia 5.2 chips). I currently have a temperature of ~105 degrees fahrenheit, roughly 1/4" above the multichip pad's surface when running the chips at 60% power. Thanks

08/31/2015, 12:55 AM	#2
theatrus 100-mile-commuter Join Date: Dec 2004 Location: almost nevada Posts: 4,721	Many LEDs are rated for operation at an 80-85C junction (die) temperature. This is of course nearly impossible to measure directly, so you back calculate based on thermal resistances. Rough guessing, I wouldn't want the heat sink base above 50C. __________________ Custom electronics purveyor. blueAcro.com Current Tank Info: 90g SPS+mixed reef (10 yrs): LEDBrick LEDs, 40g custom sump, Ca reactor, chiller, Vortech, lots of custom electronics

08/31/2015, 01:13 AM	#3
vbsaltydog Registered Member Join Date: Oct 2007 Location: Melbourne Beach, FL. Posts: 603	That seems reasonable. Thanks.