1) Calculate the size (W/L) of M1 to ensure a good matching condition of the current mirror (biasing conditions for M2 and M4 are identical). (6 points) 2) Find IO. (6 points) 3) What's the input resistance RI ? (6 points) 4) Find VI, min. (6 points) 5) Find VO,min. (6 points) 6) What's the output resistance RO? (Bonus question: Extra 10 point) Given that, VDD = 5 V, VTN = 0.4 V, kn = 100 μA/V2, λn = 0.02 V−1, (W/L)2,3 = 30, (W/L)4 = 7.5, I1 = 25 μA, IBias = 50 μA.
1) Find VO. For this part, you can ignore λn. (10 points) 2) What's the output resistance RO? You must use small-signal (ss) model to determine the output resistance. ( 4 points for SS model and 10 points for the rest) 3) If VDD increase 10% to 5.5 V, will the VO also increase 10% and why? (6 points) Given that, VDD = 5 V, VTN = 0.4 V, kn = 100 μA/V2, λn = 0.02 V−1, (W/L) = 80, R1 = 4 kΩ, R2 = 0.5 MΩ, R3 = 4.5 MΩ, and assume that the current through R2 and R3 is negligible compared to IDS.
In Fig. 4(a) and (b), VDD = 3.3 V, I1 = 10 μA, (W/L)3 = (W/L)4 = (1/0.1). Fig. 4( b) represents the I−V characteristic of the cascode current source formed by M3 and M4. (a) Determine (W/L)1 and (W/L)2 so that IA = 40 μA and VA = 2.2 V. Ignore the channel length modulation. (10) (b) Using small-signal analysis, determine the output resistance of the cascode current source when λp = 0.1/V.