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The NMOS transistors in the circuit of Fig. 1 have VTH0 = 300 mV, unCox = 0.15 mA/V2, lambda = 0 V-1, Vcc = 1.2 V, gamma = 0.45 V0.5, W = 2 um and L1 = 0.40 um. a) Sketch the current and transconductance of NMOS versus Vx(R1=0.1kohm, I1=1 mA) for the input voltage source (Vx) varying between 0V and 2Vcc. (Hint: Determine the different regions of operation of a transistor and derive a current equation for each region, then find the threshold voltage for changing the operation region. Likes below figure) b) For the circuit in Figure 3, sketch the output voltage versus Vb for the bulk voltage source (Vb) varying between 0 V and 1 V. The bulk of the transistor should be considered, phiF = 0.45 V. c) For the circuit considered in Figure 3, explain qualitatively what would happen for Vb > 1 V.

The NMOS transistors in the circuit of Fig. 1 have VTH0 = 300 mV, unCox = 0.15 mA/V2, lambda = 0 V-1, Vcc = 1.2 V, gamma = 0.45 V0.5, W = 2 um and L1 = 0.40 um. a) Sketch the current and transconductance of NMOS versus Vx(R1=0.1kohm, I1=1 mA) for the input voltage source (Vx) varying between 0V and 2Vcc. (Hint: Determine the different regions of operation of a transistor and derive a current equation for each region, then find the threshold voltage for changing the operation region. Likes below figure) b) For the circuit in Figure 3, sketch the output voltage versus Vb for the bulk voltage source (Vb) varying between 0 V and 1 V. The bulk of the transistor should be considered, phiF = 0.45 V. c) For the circuit considered in Figure 3, explain qualitatively what would happen for Vb > 1 V.

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The NMOS transistors in the circuit of Fig. 1 have VTH0 = 300 mV, unCox = 0.15 mA/V2, lambda = 0 V-1, Vcc = 1.2 V, gamma = 0.45 V0.5, W = 2 um and L1 = 0.40 um. a) Sketch the current and transconductance of NMOS versus Vx(R1=0.1kohm, I1=1 mA) for the input voltage source (Vx) varying between 0V and 2Vcc. (Hint: Determine the different regions of operation of a transistor and derive a current equation for each region, then find the threshold voltage for changing the operation region. Likes below figure) b) For the circuit in Figure 3, sketch the output voltage versus Vb for the bulk voltage source (Vb) varying between 0 V and 1 V. The bulk of the transistor should be considered, phiF = 0.45 V. c) For the circuit considered in Figure 3, explain qualitatively what would happen for Vb > 1 V.

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For the circuit in Fig.4, find the minimum voltage for Vb2 that can ensure both transistors operate in saturation. (VTH0 = 300 mV, unCox = 0.15 mA/V2, lambda = 0 V-1, Vcc = 2 V, gamma = 0 V0.5, W1 = 20 um, W2 = 50 um and L = 0.40 um, RL = 1 kohm, Ids = 1 mA)

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