| 摘要 |
An insulated gate bipolar transistor (IGBT) device is a semiconductor device comprising a main IGBT 1, a sub IGBT 20, and a current limiting circuit 30 on one chip. It has an n-channel main IGBT 1, sub IGBT 20, and sensor IGBT 2 connected in parallel, whose current is controlled by a gate signal IN, an emitter resistor RE of the sensor IGBT 2, and an n-channel MOSFET 7 to which a voltage drop of the emitter resistor RE is applied as a gate voltage for fast discharging gate capacities C1, C2, and C20 of the IGBT 1, IGBT 2, and IGBT 20. Threshold voltage VTHB of the sub IGBT 20 is set high on the order of 1 V as compared with threshold voltage VTHA of the main IGBT 1 and the sensor IGBT 2. When a load 6 is discharged, the gate capacities C1, C2, and C20 are discharged dominantly, thus only the sub IGBT 20 is cut off and the main IGBT 1 and the sensor IGBT 2 perform the current limit operation, so that the load short-circuiting current can be stepped down drastically.
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