| 摘要 |
PURPOSE:To prevent leak of an input signal and to attain a high gain by connecting a beta correcting resistance and a feedback capacitor to a transistor TR which supplies a bias current due to current mirror constitution through an input signal leak preventing resistance. CONSTITUTION:The base of a TRQ11 for bias and the base of a TRQ12 for amplification are connected through resistances R11 and R12. The TRQ11 has the emitter earthed and has the collector connected to a power source VCC through a current source Is and supplies the bias current due to the current mirror constitution to the base of the TRQ12 through an input signal leak preventing resistance R12. The beta correcting resistance R11 for compensating fall of the gain and a feedback coupling capacitor C11 for cancelling a high frequency noise are inserted between the collector and the base of the TRQ11.
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