(a) Show that introducing a cascode transistor to an IC CS amplifier whose bandwidth is limited by the interaction of Rsig and the input capacitance, and whose load resistance is equal to ro, increases the dc gain by approximately a factor of 2 and fH by the factor N,
N = Cgg + 1/2(gm ro)Cgd / Cgg + 3Cgd
Assume that the bandwidth of the cascode amplifier is primarily determined by the input circuit.
(b) If Cgd = 0.1Cgs and the dc gain of the CS amplifier is 50, what is the value of N?
(c) If VA = 10 V, μnCox = 400 μA/V2, and W/L = 10, find VOV and ID at which the transistors must be operating.