| 摘要 |
PURPOSE:To reduce the degree of saturation of a main transistor immediately after turn on by a method wherein the parallel circuit of a capacitor and a discharging resistor is connected in parallel to more than one of a plurality of collector catch diodes. CONSTITUTION:A capacitor 10 and a discharging resistor 11 are connected in parallel to the collector catch diode 9 of a plurality of collector catch diodes 8, 9, which are connected in series. When an on-off commander 13 outputs a command, a forward bias resistor 6 is put ON to provide the base of a main transistor 3 with forward bias current and turn on a main transistor 3. Base current 1a, rushing into the base, is reduced by increasing the on-voltage of the main transistor 3 upon only the turn on whereby the degree of saturation of the main transistor 3 immediately after the turn on is reduced. According to this method, high-speed and high-frequency switching may be effected. |
