This document specifies a test method (referred to herein as "Transient Dual Interface Measurement") to determine the conductive thermal resistance "Junction-to-Case" R_?JC (?_JC) of semiconductor devices with a heat flow through a single path, i.e. semiconductor devices with a high conductive heat flow path from the die surface that is heated to a package case surface that can be cooled by contacting it to an external heat sink.

The thermal resistance measured using this document is R_?JCx or ?_JCx, where x denotes the package case side, where the heat is extracted, usually top (x= top) or bottom (x= bot) side.