Thermal design can be a more significant determinant of total light output in high-brightness LED designs than the electrical design. LED lifetimes can decrease as temperatures rise, and at high enough temperatures, LED efficacy decreases. To ease the thermal design challenges, Nationals new PowerWise® LM3424 LED driver features thermal foldback which reduces regulated current through the LEDs as the temperature increases.
LM3424 Thermal Foldback – Easy Thermal Control for LED Lighting - [Link]
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