Here’s a tutorial from Maxim describing the thermal specifications in IC packages. All the devices used in a project dissipate heat, and if not properly cooled they will fail. This article will bring you closer to understanding the thermal specs quoted in datasheets.
Thermal characterization of packages is critical for the performance and reliability of IC applications. This article describes the standard thermal package properties: thermal resistance (known as “theta” or Θ), ΘJA, ΘJC, and ΘCA. Thermal calculations and references for more information on thermal management are provided.