随着电子技术日益迅猛的发展，电子设备的体积趋于微型化，系统趋于复杂化，越来越多的电子元器件被封装于更小的空间里，同时印制电路板的密度也变得越来越大。由于印制电路板中元器件密度过大会引起热密度增大，从而使得元器件温度上升，而元器件温度过高会降低其可靠性... With the rapid development of electronic technology, the volume of electronic equipment tends to be miniaturized and the system tends to be complicated. More and more electronic components are packaged in a smaller space, and the density of printed circuit boards also changes Getting bigger and bigger Due to excessive density of components in the printed circuit board caused by increased heat density, making the temperature rise of components, and components temperature is too high will reduce its reliability ...