A new IGBT with a monolithic over-current protection circuit

A new IGBT structure with a monolithic overcurrent sensing and protection circuit has been developed. The feature of this device is a novel integration of a sensing and protection circuit which consists of a sensing IGBT, lateral n-MOSFET, polycrystalline silicon diode and resistor with an IGBT structure. The conventional IGBT fabrication process is available to this device with only one more photomask. Comparison of not only a short circuit safe operating area but both a trade-off characteristics between an on-state voltage drop and a turn-off loss and reverse biased safe operating area with a conventional IGBT has been investigated. Since exhibiting a large short circuit safe operating area without deterioration of any other device characteristics, this device can be applied to not only a soft switching application like voltage resonant circuit but a hard switching application like snubberless inductive load circuit.