Question 6.14: Can we construct a (two-terminal) inductor from a source fol...

Yes, we can. Called an “active inductor,” such a structure is shown in Fig. 6.30(a), providing an inductance of (C_{GS2}/g_{m2})(R_S − 1/g_{m2}). But the inductor is not ideal because it also incurs a parallel resistance equal to R_1 = R_S = 1/g_{m2} and a series resistance equal to 1/g_{m2}. Figure 6.30(b) depicts an application of active inductors: the inductance can partially cancel the load capacitance, C_L , at high frequencies, thus extending the bandwidth. However, the voltage headroom consumed by M_2 (= V_{GS2}) limits the gain. Also, C_{G D2}, which has been neglected in our analysis, limits the bandwidth enhancement.