Repeat Problem 7.40 including short-channel effects with ε_c= 1.5 × 10⁶V/m.

Data from Prob. 7.40:

Use the zero-value time-constant method to estimate the small-signal dominant pole for the current gain of the MOS cascode current mirror of Fig. 4.9. Assume an input ac current source in parallel with I_IN and a zero load impedance with V_out = V_GS3 + V_GS4. The bias current I_IN = 100 µA. Compare your answer with the f_T value of the devices. Device parameters are μ_nC_ox = 60 µA/V², γ = 0, λ = 0, V_t = 0.7 V, W = 10 µm, L_eff = 1 µm, C_gs = 20 fF, C_gd = 3 fF, C_sb = C_db = 10 fF at the bias point. Compare your answer with a SPICE simulation of the bandwidth of the circuit and use SPICE to find the bandwidth for I_IN = 50 µA and I_IN = 200 µA.

Fig. 4.9:

Vpp IOUT M2 M4 VOUT VIN M1 M3 (a) IOUT Vmin Von - VOUT ` M1 active, M2 in triode region Both M, and M2 in triode region (b)