| 摘要 |
PURPOSE:To suppress the generation of excessive magnetic bubble produced at a generator, by providing a time constant set circuit shaping slowly only the fall waveform of a pulse current between a TTL signal input circuit and an emitter follower constant current source circuit. CONSTITUTION:When an output transistor (TR) Q1 of the emitter follower constant current source circuit 3 is turned on, a reference voltage Vref based on a reference voltage circuit 2 is impressed to the emitter, and a current determined with a current set resistor RE connected to the emitter and the emitter voltage flows to a load resistor RL located at the outside of an integrated circuit connected to the collector, so long as the output TRQ1 is not saturated. In this case, since a time constant set circuit 4 comprising a diode D3, a capacitor CT and a resistor RT is connected to the base of the output TRQ1, the base potential of the output TRQ1 is increased to a voltage charged up with the capacitor CT and the fall waveform of an output pulse current I is a mild waveform. |
