In this amplifier circuit, the high and low DC voltage sources are: VD

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In this amplifier circuit, the high and low DC voltage sources are: VDD = 5 V and VSS = −5 V respectively. Consider that all three external capacitors have high values. The PMOS transistor has a threshold voltage equal to Vt = −1 V and kp = kp′(W/L) = 0.4 mA/V2, and the NMOS transistor has a threshold voltage Vt = 1 V and a kn = kn′(W/L) = 2 mA/V2. It was shown in HW#7 that the DC drain voltage of the PMOS transistor is −0.2 V and the DC source of the NMOS transistor is −2 V. a) Perform the small signal analysis of this circuit and determine the voltage gain: AV = Vo/Vi b) Determine the input and output resistance of this amplifier Rin and Rout . c) Discuss what is the purpose of the part of the circuit between CC2 and CC3 which includes the NMOS transistor in this amplifier design. d) Determine the parameters of a simple voltage amplifier model (discussed in chapter 1) which will represent this amplifier. Note that the parameters of the simple voltage amplifier excludes any series resistance of the external source ( Vi ) (in this case it is zero anyway) and the load resistance (in this case RL = 2 kΩ ). e) Using the simple model from part (c) determine the voltage gain AV = Vo/Vi and see if it agrees with the answer of part (a). VDD

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In this amplifier circuit, the high and low

D C

voltage sources are:

V_{D D} = 5 V

and

V_{S S} = - 5 V

respectively. Consider that all three external capacitors have high values. The PMOS transistor has a threshold voltage equal to

V_{t} = - 1 V

and

k_{p} = k_{p}^{'} (W / L) = 0.4 m A / V^{2}

, and the NMOS transistor has a threshold voltage

V_{t} = 1 V

and a

k_{n} = k_{n}^{'} (W / L) = 2

m A / V^{2}

. It was shown in HW#7 that the DC drain voltage of the PMOS transistor is

- 0.2 V

and the DC source of the NMOS transistor is

- 2 V

. a) Perform the small signal analysis of this circuit and determine the voltage gain:

A_{V} = V_{0} / V_{i}

b) Determine the input and output resistance of this amplifier

R_{in}

and

R_{out}

. c) Discuss what is the purpose of the part of the circuit between

C_{C 2}

and

C_{C 3}

which includes the NMOS transistor in this amplifier design. d) Determine the parameters of a simple voltage amplifier model (discussed in chapter 1) which will represent this amplifier. Note that the parameters of the simple voltage amplifier excludes any series resistance of the external source (