The amplifier circuit shown below uses a silicon transistor. The capacitors Cc and CE can be assumed to be short at signal frequency and the effect of output resistance r0 can be ignored. If CE is disconnected from the circuit, which one of the following statements is TRUE?
Options
A. The input resistance Ri increases and the magnitude of voltage gain Av decreases
B. The input resistance Ri decreases and the magnitude of voltage gain Av decreases
C. Both input resistance Ri and the magnitude of voltage gain Av decrease
D. Both input resistance Ri and the magnitude of voltage gain Av increase
Correct Answer
The input resistance Ri increases and the magnitude of voltage gain Av decreases
Explanation
Given circuit after removing CE will behave as current-series feedback.
Overall voltage gain will decrease as feedback signal comes into picture and since it is current-series feedback, input impedance increases.
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