Answer Happy

Q3 (a) An amplifier system without feedback has the following specifications: Open loop gain: 90 Input impedance: 25kQ Output impedance: 5k (i) (ii) If the amplifier system employs negative feedback and the close loop gain is 9.5, calculate the system feedback factor, f. (2 marks) Suppose the negative feedback topology used for the amplifier system in Q3(a)(i) is a current shunt feedback, determine the amplifier, input impedance and output impedance of the amplifier with feedback. (6 marks)
(b) Figure Q3(b) is a block diagram of an amplifier (dotted box) utilizing negative feedback. For this figure: (i) (ii) (iii) Determine the type of the amplifier and the feedback topology used. Discover the relationship between the output impedance without feedback (Zo) and the output impedance with feedback (ZOF). (8 marks) Analyze how the negative feedback improves the input impedance of the amplifier. Vs (~ Z₁P G + A V₁ I + Vp N Z₁ B 1000V, Figure Q3(b) W Zo Io (2 marks) RL ZOF + Vo (2 marks)