| 摘要 |
PURPOSE:To increase the switching speed, by providing a means producing a fixed potential between the emitter of the 2nd transistor (TR) of npn type in which a load element is inserted to the collector of the 1st TR of npn type taking the emitter as the input terminal through the short circuit of base and collector, and the reference potential. CONSTITUTION:When an input signal In is at a low potential V1L, since a current flows to the emitter of a TR21 via a load resistor 22, the base potential of the TR21 is at V1L+VBE. On the other hand, when the input signal In is at a high potential V1H, the base potential of the TR21 is at V1H+VBE. Since the TR12 is not conductive, if the base potential is not more than the VB+VBE, where the VB is the output voltage of a constant voltage power supply 23, the switching control of the TR12 can be made, by setting the VB to a value within the V1L and V1H. Since the base and collector of the TR21 is shorted and the voltage between the collector and the emitter is not zero, the TR21 is not in saturation operation. |
