申論題

5. The schematic and small-signal equivalent circuit of a two-stage op amp are shown in Fig. 5(a) and (b), respectively. Assume the magnitude of early voltage V_A is identical for all MOSFETs. The circuit parameters are specified as

(c) It is found that ω_t = ω_z fork = 1. Calculate the phase margin of the op-amp for k= 2.[10%]