2.1.4.4 Theta-JC

Junction-to-case thermal resistance (θJC) measures the ability of a device to dissipate heat from the surface of the chip to the top or bottom surface of the package. It is applicable for packages used with external heat sinks. Constant temperature is applied to the surface in consideration and acts as a boundary condition. This only applies to situations where all or nearly all of the heat is dissipated through the surface in consideration.