| 摘要 |
PURPOSE:To simplify a circuit by providing a 2nd switching element in parallel to one resistance of a resistance serial circuit connected between the gate of an insulating gate bipolar transistor(IGBT) and a voltage source. CONSTITUTION:This device is provided with a 1st switching element Q1 and a voltage limit element ZD respectively connected between the gate and emitter of the IGBT, two or more resistances R1 and R2 serial circuit connected between the gate of the IGBT and a power source having a higher voltage than an IGBT on-voltage, and the 2nd switching element Q2 connected in parallel to at least one resistance R2 of the resistance serial circuit. Therefore, at the time of switching the 1st switching element Q1 from an on-state to an off-state, the 2nd switching element Q2 is turned on for a moment to short-circuit the resistance R2 connected in parallel to the 2nd switching element Q2 to lower impedance, and the rising of a voltage added to the gate of the IGBT is quickened. Thus, necessary characteristic is obtained by the simple circuit. |
