and Moon-Hwan Chang
Center for Advanced Life Cycle Engineering (CALCE), University of Maryland, College Park, MD 20740, USA
Some like it hot, others do not. And those others for sure include the designers of products that contain light-emitting diodes (LEDs). This book is about thermal management of LEDs and especially LED applications. The main question to be addressed is: Why do we need thermal management? As Belady put it eloquently in 2001 [Belady and Minichiello, Electronics Cooling Magazine, May issue, 2003]:
The ultimate goal of system thermal design is not the prediction of component temperatures, but rather the reduction of thermally associated risk to the product.
Hence, the objectives of a designer are not in the first place to calculate or measure temperatures, but to keep the lifetime beyond x years, to keep the colour point within margin y, and to raise the efficiency to z %. And indeed, these objectives, determining the quality of LED-based products, are linked to the junction temperature. This is the main reason why a book on LED thermal management starts with an introductory chapter on LED reliability issues.
Parts of this chapter have been sourced from a chapter in a book on Solid State Lighting Reliability [Pecht and Chang, Solid state lighting reliability: components to systems, Springer, New York, pp. 43.110, 2013].
Complete article available from the publisher and to the CALCE Consortium Members.