# Heatsink Selection

Hello,

I’m looking for a recommendation on a heatsink for a lighting application. I have a 10" x 10" grid of LEDs with a total DC wattage of about 430W. As i understand from other discussions about 40-50% of that power will be thermal power (175W-200W). It’s a natural convection application with an ambient of 35C while trying to keep LEDs at a Tc of 65C or better (if possible). I’m looking for a recommendation on the type (extruded, folded fin etc.) and heatsink size.

thanks,

@DigiKey_Internal
Is there any one with more experience with circuit design able to help?

There are many thermal calculators out there where you enter in the degC/W for each item and it works out the math in trying to resolve if you can meet your thermal budget or not.

One example…

Maximum luminous efficacy is 683 lumens/watt. If the LEDs in question develop 120 lm/W, roughly (683-120)/683=82% of electrical input gets converted to heat, as a conservative estimate.

Divide the desired maximum temp rise by the thermal load to find a thermal resistance target; 30°C/200W = 0.15°C/W for example, which would be a rather aggressive target for a natural-convection application. Something like the 345-1962-ND might get one there…