트랜지스터 대수증폭기의 해석

Analysis of Transistorized Logarithmic Amplifier

하이브리드-π 등가회로를 사용하여 공통 에미터 트랜지스타를 궤환소자로 하는 대수증폭기의 전달함수와 안정에 필요한 입력용량 C1의 최소치를 유도하였다.

Detailed analysis has been developed concerning the transfer function and stability condition of the logarithmic amplifier using a common emitter transistor as a feed-back element. The analysis shows that input current vs output voltage transfer characteristics is accurately ogarithmic through entire operating current, and the time constant depends on input capcitance and collector-emitter equivalent resistance. Also the minimum value of imput capacitance required to stabilize the system is derived.