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Consider the following amplifier operating at 300 K. The transistor M1 has μnCox = 250 μA/V2 and Vth = 0.4V. You may assume that M1 operates in saturation region and neglect its channel length modulation (λ = 0). The supply voltage VDD is 1.8V. (a) Find the expression for the input resistance (Rin) assuming that M1 has the transconductance of gm in saturation region. (b) Find the expression for the voltage gain AV=Vout /vin. (c) Explain the phase relationship between the vin and Vout signals. In other words, are they in phase or out of phase? Explain the reason why. (d) If this amplifier stage must provide an output resistance of 500 Ω, what is the maximum allowable value for ID of M1 that keeps M1 in saturation? (e) For the ID value obtained from (d), calculate the required value of W/L that makes the voltage gain Av equal to 10. (f) Calculate the maximum load capacitance (Cout ) that the amplifier can drive at its output while keeping its −3dB bandwidth above 100 MHz.

Consider the following amplifier operating at 300 K. The transistor M1 has μnCox = 250 μA/V2 and Vth = 0.4V. You may assume that M1 operates in saturation region and neglect its channel length modulation (λ = 0). The supply voltage VDD is 1.8V. (a) Find the expression for the input resistance (Rin) assuming that M1 has the transconductance of gm in saturation region. (b) Find the expression for the voltage gain AV=Vout /vin. (c) Explain the phase relationship between the vin and Vout signals. In other words, are they in phase or out of phase? Explain the reason why. (d) If this amplifier stage must provide an output resistance of 500 Ω, what is the maximum allowable value for ID of M1 that keeps M1 in saturation? (e) For the ID value obtained from (d), calculate the required value of W/L that makes the voltage gain Av equal to 10. (f) Calculate the maximum load capacitance (Cout ) that the amplifier can drive at its output while keeping its −3dB bandwidth above 100 MHz.

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Consider the following amplifier operating at 300 K . The transistor M 1 has μ n C o x = 250 μ A / V 2 and V t h = 0.4 V . You may assume that M 1 operates in saturation region and neglect its channel length modulation ( λ = 0 ) . The supply voltage V D D is 1.8 V . (a) Find the expression for the input resistance ( R i n ) assuming that M 1 has the transconductance of g m in saturation region. (b) Find the expression for the voltage gain A V = V out / v in . (c) Explain the phase relationship between the v in and V out signals. In other words, are they in phase or out of phase? Explain the reason why. (d) If this amplifier stage must provide an output resistance of 500 Ω , what is the maximum allowable value for I D of M 1 that keeps M 1 in saturation? (e) For the I D value obtained from (d), calculate the required value of W / L that makes the voltage gain A v equal to 10 . (f) Calculate the maximum load capacitance ( C out ) that the amplifier can drive at its output while keeping its − 3 d B bandwidth above 100 M H z .

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