Question

Which of the following statements is FALSE? O A Negative feedback reduces the gain of an amplifier DB. Op-amp circuits usually employ voltage sensing at the output OC. Negative feedback can lead to instability D Negative feedback reduces the sensitivity of the gain of an amplifier to changes in the parameters of the amplifier's O E. Negative feedback increases the input resistance and reduces the output resistance of an amplifier

Answer 1

"Which of the following statements is false A) Negative feed back reduced the gain of * an amplifier The general expression for feedback system implies T. F = G(s)/1 plusminus G(s) H(s) + rightarrow -ve (Negative) feed back - rightarrow +ve (positive) feed back so, for -ve feedback T.F = G(s)/(1 + G(s) H(s)} Hence negative feedback reduced the gain of the amplifier c) Negative feed back can lead to instability In general by introducing feedback There will be some oscillations in system with the presence of feedback (oscillations) stability reduce hence by introducing negative feedback can lead to instability D) Negative feedback reduces the sensitivity of the gain of an amplifier to changes in the parameter of the amplifier components implies sensitivity with response to parameter variation in operation \r\n system is very high that is amount 100% implies By introducing feedback the closed loop sensitivity with respect to parameter variation reduced i) w r t parameter variation ""G"""