| 摘要 |
PURPOSE:To eliminate the influence of an increase or decrease of a constant current source by generating the emitter current of an npn transistor Tr by a current mirror circuit composed of two pnp Trs and a resistance and supplying a constant current to the npn Tr. CONSTITUTION:An npn Tr 10 has its base connected to a resistance 7 and the collector of an npn Tr 8 and a Tr 1 has its emitter connected to the constant current source 2 and its collector and base short-circuited. Further, a resistance 12 is connected between the collector-base connection point of the Tr 11 and a low potential terminal 4. Then, the base of a Tr 14 is connected to the base-collector connection point of the Tr 11 and the collector is connected to the collector of a Tr 10. Further, the emitter of a Tr 13 is connected to the constant current source 2, the base is connected to the collector of the Tr 10 and the collector of a Tr 14, and the collector is connected to the low potential terminal 4. In this constitution, a stabilized output voltage is determined by the sum of the voltage drop across the resistance 7 and the base- emitter voltage of the Tr 10. Consequently, an increase of the constant current source 2 is absorbed by the Tr 13, so the base-emitter voltage of the Tr 10 becomes stable.
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