Question

Problem 1: Consider the circuit shown in Figure 1. This is called a "telescopic cascode" amplifier. Assume that all transistors are in saturation. Do not ignore channel length modulation. Assume that

all nMOS transistors have small signal parameters, gm,n and Ton, and all pMOS transistors have small signal parameters, gm.p and ro.p. Assume that gm,xfo,x >> 1 for x = n, p. (a) Calculate Rout. (b) Calculate Vout/Vin. (c) Calculate the range of values for Vout such that all transistors remain in saturation. Assume that all nMOS transistors have the same overdrive, Vod,n = VGS,n - VTH,n, all pMOS transistors have the same overdrive, Vod,p = VSG.p - VTH.pl, and the supply is VDD. (5+5+5= 15 points) VGH Vin" T J 4 M2 MI Figure 1 Vout

Fig: 1