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+//Example 1.25
+clc
+disp("Step 1: Identify topology")
+disp("By making Vo = 0, feedback current becomes zero. Hence it is a voltage sampling. The feedback is fed in shunt with the input signal and thus the topology is voltage shunt feedback")
+disp("")
+disp("Step 2 and Step 3: Find input and output circuit")
+disp("To find input circuit, set Vo = 0. This places resistor R across the input. To find output circuit, set V_i = 0. This places resistor R across output. The resultant circuit is shown in fig 1.72")
+disp("")
+disp("Step 4: Replace FET with its equivalent circuit as shown in fig 1.73")
+disp("")
+disp("Step 5 : Find open loop transresistance")
+disp("R_M = Vo/I_s = -g_m*V_gs*R_eff/I_s")
+reff=(40*200*10)/((200*10)+(400)+(40*200))
+format(5)
+disp(reff,"where  R_eff(in k-ohm) = r_d || R || R_D =")
+disp("and  V_gs = I_s*R_i = I_s * R_s||1M||R")
+disp("          = I_s * 10K||1M||200K")
+disp("          = 9.43*10^3 I_s")
+rm=-2.5*9.43*7.69
+format(7)
+disp(rm,"R_M(in k-ohm) =")
+disp("")
+disp("Step 6: Calculate beta")
+b=-1/(200*10^3)
+format(7)
+disp("beta = I_f/Io = V_i-Vo/Vo*R =")
+disp(b,"     = -1/R =            because (Vo > V_i)")
+disp("")
+disp("Step 7: Calculate D, R_Mf, A_vf, R_of, R''_of")
+d=1+(5*181.29*10^-3)
+format(4)
+disp(d,"D = 1 + beta*R_M =")
+rmf=-181.29/1.9
+format(7)
+disp(rmf,"R_Mf(in k-ohm) = R_M/D =")
+avf=-95.415/10
+format(7)
+disp(avf,"A_vf = V0/V_s = Vo/I_s*R_s = R_Mf/R_s =")
+ri=(10*1000*200)/((1000*200)+(10*200)+(1000*10))
+format(5)
+disp(ri,"R_i(in k-ohm) = R_s || M || R =")
+rif=(9.43)/1.9
+format(6)
+disp(rif,"R_if(in k-ohm) = R_i/D =")
+ro=(40*200*10)/((200*10)+(400)+(40*200))
+format(5)
+disp(ro,"R''_o(in k-ohm) = r_eff = r_d || R || R_D =")
+rof=(7.69/1.9)
+format(2)
+disp(rof,"R''_of(in k-ohm) = R''_o/D =")