What are the important points in heat management of regulators?
There are three key points to heat management that are especially critical in linear regulators: (1) Don”t burn yourself (the surface of the regulator can get hot, especially the metal tab!); (2) Don”t melt something next to the regulator (same reason); (3) Don”t plan to run the regulator hotter than its Operating Maximum Temperature (it will shut down). Heat affects more than just the regulator. Heat conducted down a poorly heatsinked regulator”s leads can damage the PCB material and solder connections over time. Nearby electrolytic capacitors may become damaged at the high temperatures. Heat management of a regulator follows a simple equation: Tj = Ta + (Pd x ThetaJA) where Tj is the internal (junction) temperature of the IC, Ta is the ambient temperature near the IC, Pd is the power dissipated by the IC, and ThetaJA is the thermal resistance from the internal junction of the IC to its ambient environment. “Heatsinking” is the process of reducing ThetaJA so that the IC internal t
