| 摘要 |
PROBLEM TO BE SOLVED: To eliminate overshootings, and to protect a semiconductor device from an overvoltage and to prevent breakage of the semiconductor device, by connecting a voltage clamping circuit between the collector and gate of a semiconductor device in its vicinity with distributing wires which are shortest. SOLUTION: For example, a reverse conducting pressure-welded type IGBTQ are connected from its both surfaces through pressure welding by a collector-side cooling substance 11 and an emitter-side cooling substance 12. To the side surface of the collector-side substance 11 on the same side as a surface from which a gate G1 and auxiliary emitter E1 of the IGBTQ protrude, a diode D-side element of a voltage-clamping circuit 10 is directly connected, using a copper bar 13 whose inductance is extremely small. Additionally, the collector-side substance 11 is conductive and electrically connects the copper bar 13 to the collector side of the IGBTQ via the collector-side substance 11. A zener diode ZD-side terminal of the clamping circuit 10 is directly connected to the gate G1 of the IGBTQ by the shortest distributing wire. Consequently, the wiring inductance is made small, and the oscillation of a resonance current is made small. |
