| 摘要 |
PURPOSE:To perform a stable switching operation by selecting the turn ratio of the tertiary winding to the secondary winding of a feedback current transformer so that a prescribed relation may be held between the diode voltage and respective saturation voltages across the emitter and the collector and across the base and the emitter. CONSTITUTION:Primary winding N1, secondary winding N2 and tertiary winding N3 of feedback current transformer T are connected in series, and winding N1 is connected to the emitter of transistor TrQ, and winding N2 is connected between the base and the emitter, and winding N3 is connected between the collector and the base through diode D. When signals are applied to terminal BT or a dotted-line control winding to turn on TrQ, TrQ is turned on rapidly; and when the saturation voltage between the emitter and the collector, the saturation voltage between the base and the emitter, the voltage of diode D are denoted as VCE(sat), VBE(sat) and VD respectively, N3/N2 is so selected that expression (7) may be true, As a result, a stable switching operation can be performed. |
