| 摘要 |
The specification discloses a transition speed up circuit including an input transistor (14) for receiving a variable input voltage (VIN). An output transistor (16) is connected to the input transistor (14) to receive turn on current. A first diode (32) is connected at its cathode to the collector of the input transistor (14). A resistor (46) is connected between the anode of diode (32) and the output terminal (18). A speed up transistor (42) is connected at its emitter to the collector of input transistor (14) to supply speed up current through input transistor (14) to output transistor (16). A second diode (44) is connected between the base of speed up transistor (42) and the junction of first diode (32) and resistor (46). The speed up current terminates when the voltage at the output terminal (18) fails to a level determined by the value of resistor (46). |
