What Is Hot Spot in SMT Assembly?
A Hot Spot is an area that gets too much heat and results in warped, blistered or even burnt boards. Generally, this is caused by large areas of copper (Copper Pour) in specific areas. These areas heat up quicker and become hotter than other areas of the PCB resulting in unbalanced temperatures across the PCB. To avoid Hot Spots ensure the copper is balanced across the PCB. This is contrast to Cold Spot.
Both the PCB design and an optimized thermal profiling will be the best solutions to prevent such reflow failure.