11.5 For the feedback voltage amplifier of Fig. 11.9(c):
(a) Find an expression for β.
(b) Neglecting the MOSFET ro, find an expression for the loop gain Aβ. (Hint: Break the loop at the gate of Q.)
(c) Find an expression for the open-loop gain A.
(d) For gm = 4 mA/V, RD = 10 kΩ, R1 = 20 kΩ, and R2 = 80 kΩ, find the values of β, Aβ, A, and the closed-loop gain Af . What would Af be if Aβ were much greater than unity?