The saturation voltage characteristics of both the ‘V’ and ‘H-B’ across the operating temperature range are shown on this slide. Note that both exhibit a “slightly positive Vce saturation” temperature coefficient which is a desired characteristic of the new Trench Gate Field Stop technology devices. This allows devices to be paralleled and current share without going into a thermal runaway condition that will cause them to fail. Effectively this works when one device starts to carry more current; it will heat up causing it to carry less current because of its rising Vce saturation voltage. This then forces other devices in parallel to take additional current. The mechanism causes the current flow in all of the paralleled devices to equalize, or have an equal share of current in each device, never allowing a thermal runaway condition to occur. This feature is especially useful when employing multiple paralleled die to build IGBT modules with high current ratings. A thermal runaway condition can occur in ‘negative temperature coefficient’ Punch Through Planar technology IGBTs. This happens when the more current a single device carries, the hotter it gets and the lower its Vce saturation becomes, encouraging the devices to allow more current to flow though it than the others in parallel, eventually taking all of the current flow and causing it to fail as it conducts more that the maximum current rating.