Development of high power, high intensity, surface mount white light LEDs has led to widespread adoption of this semiconductor as a light source in homes, traffic signals, decorative lighting, commercial spaces, automobile headlights and spot lighting. High power LEDs are the most efficient in terms of durability and light output but one drawback is that they dissipate a lot of heat. Metal backed PCB assemblies are commonly used to mount surface mount power LEDs where the metal works as a heat sink. The metal backing protects the LED, the board and other components from excessive heat buildup and premature failure.
The metal backing may be a thick continuous layer of copper sufficient for low power LEDs. High power LEDs typically use separate, thick aluminum metal backed PCB assemblies for a small, compact size and better thermal dissipation characteristics. A plain aluminum sheet is used or a ribbed aluminum heatsink may be affixed to the length of the PCB. These assemblies are useful in any application where thermal dissipation is needed, not just LEDs. Robust industrial devices may have ribbed metal PCB enclosures to which the PCBs are affixed. The metal PCB enclosure serves as a heat sink, resulting in a smaller footprint. PCB enclosures may be air and water tight to keep the electronic components fully protected. Plastic PCB housing is normally used for instrumentation and display devices where thermal dissipation is not an issue. Denis Ferranti is a Professional PCB housing supplier and specializes in contract PCB services. It supplies a range of quality metal and plastic DIN PCB enclosures.