| 摘要 |
PURPOSE:To improve the isolation by providing a constant current source between an emitter of a feedback transistor (TR) and a prescribed reference potential and an emitter of an output stage amplification TR and said potential and adopting a circuit of the Darlington type for the output stage amplifier section. CONSTITUTION:The constant current source 12 is provided to the emitter of the TR9, and even when the emitter voltage of the TR9 is inverted to the base voltage of the TR1 in terms of AC operation, a current flowing from the base of the TR1 to the emitter of the TR9 is absorbed up to a current value decided by the constant current source 12. When the voltage at an input (a) rises, the voltage at an output (b) descends and reaches the saturated voltage, then the cut-off of the TR9 until reaching the saturated output voltage is prevented by setting the current value of the constant current source 12 to absorb the current decided by the inverting voltage impressed to the resistor 6. Moreover, a base current of TR200 is amplified and supplied by a TR201. |
