| 摘要 |
PURPOSE:To obtain an output current steeply changed by turning on an output transistor (TR) or a dummy output TR depending on the on/off of a pulse input signal so as to prevent generation of delay when the output TR is turned on. CONSTITUTION:When a pulse input signal is given, switching control TRs 4, 8 are turned on and off, emitter follower circuits 5, 6 are inactivated and activated respectively, an output TR1 is turned off, a dummy TR7 is turned on and a dummy current decided by the ratio of an input reference voltage VR of a differential amplifier 3 to a resistor 2 flows to the emitter resistor 2. On the other hand, when the input signal is not given, the TRs 4, 8 are turned off and on, the circuits 5, 6 are activated and inactivated, the TR1 is turned on, the TR7 is turned off, and an output current decided by a ratio of the voltage VR to the resistor 2 flows to the TR1. |
