Consider the transconductance feedback amplifier shown in given Figure with RD = 1.6 k Ω and RL = 248 Ω.
The transistor parameters are VT N = 0.5 V, VT P = -0.5 V, Kn = 2 mA/V2, Kp = 10 mA/V2 , and λn = λp = 0. The LED turn-on voltage is Vγ = 1.6 V.
Assume the LED smallsignal resistance is rf = 0. The current source is ideal.
(a) Determine the quiescent values of VD1, IDQ3 and VG2.
(b) Derive the small-signal transconductance function Ag f = Io/Vi .
(c) Calculate the value of Ag f = Io/Vi .
