High turn-off current capability of parallel-connected 4.5 kV trench-IEGTs

The turn-off characteristics of parallel-connected 4.5 kV trench injection enhanced gate transistors (IEGTs) are discussed. The influence of the gate circuit parameters on turn-off current balance was examined in order to realize high turn-off current capability. It is concluded that the reduction of the gate parasitic inductance is important for uniform turn-off operation. At the optimum gate circuit condition, it is shown that the maximum turn-off current increases in proportion to the number of IEGT chips. As a result, a 1300 A turn-off current capability at T/sub j/=100/spl deg/C is realized using nine parallel-connected IEGT chips in an inductive load circuit and without a snubber circuit.