An analytical method of analyzing insulated-gate bipolar transistor (IGBT) current–voltage characteristics is established in this paper. Important internal device parameters such as the injected carrier concentrations, electron and hole current densities and depletion length of the drift region are calculated as functions of the terminal voltages. The parasitic transistor current gains αnpn and αpnp are also extracted as functions of applied voltages. The temperature effect on both latch-up criteria can also be predicted from this method.