Chapter 12, Problem 12.13EP

Consider the circuit in Figure 12.39, with transistor parameters $V_{TN}=0.8\text{V},K_n=1.5\text{mA}/{\text{V}}^2,$ and $\lambda =0.(\text{a})(\text{i})$ Find the open-loop gain for $R_F=\infty .$ (ii) Find the closed-loop gain for $R_F=47\text{k}\Omega .$ (b) Repeat part (a) if the conductance parameter decreases by 15 percent to $K_n=1.275\text{mA}/{\text{V}}^2.$ What is the percent change in the magnitude of each gain factor? (Ans. (a) (i) $A_v=-3.528$ (ii) $A_{vf}=-1.204$

(b) (i) $A_v=-3.0,-15\%$ change; (ii) $A_{vf}=-1.107$ , $-8.06\%$ change)

Figure 12.39 Circuit for Exercises Ex 12.13 and Ex 12.14