(Solved): The common source amplifier with source degeneration shown below has the following values: \[ \begi ...

The common source amplifier with source degeneration shown below has the following values: \[ \begin{array}{l} R_{s}=100 \mathrm{ohms} \\ V_{D D}=1.8 \mathrm{~V} \\ V_{\text {th }}=0.4 \mathrm{~V} \\ R_{1}=23 \mathrm{k} \mathrm{ohm} \\ R_{2}=20 \mathrm{k} \mathrm{ohm} \\ I_{d s}=1.5 \mathrm{~mA} \\ \lambda=0 \mathrm{~V}^{-1} \end{array} \] a) (10 points) Find the value of \( R_{D} \) to make the gain of the amplifier \( A v=-4 \). Verify that the device M1 is in saturation. b) (10 points) You add a large capacitor \( \mathrm{C} 2 \) across the source resistance. Assuming this capacitor acts as a short at the frequencies of interest, and using the value of \( R_{D} \) found in part \( a \), what is the gain now?