Show that the CMOS circuit of Fig. 10.25 realizes a square-law transfer characteristic from V_ito I_o assuming that the MOSFETs have square-law characteristics. Specify the range of V_iover which this holds. (The bias analysis of Section 9.6.4 applies.) All PMOS devices have W/L=60 and all NMOS haveW/L=20. Device data are μ_nC_ox= 60µA/V², μ_pC_ox=20µA/V², V_tn=0.7V, V_tp= ˆ’0.7V, γ = 0, and λ= 0.

Use SPICE to verify your result by plotting and evaluating the dc transfer characteristic. Then apply an input sine-wave voltage drive atV_i within the square-law range and examine the first and second harmonics inI_oand comment.

Fig. 10.25:

Transcribed Image Text:

VDD = 5 V M10 M9. M4 Мз M2 M1 V; M8 M7. M6 M5 14 50 μΑ 50 μΑ