Chapter 3, Problem 3.23P

An NMOS transistor has parameters $V_{TO}=0.75\text{V}$ , ${k^{\prime }}_n=80\mu {\text{A/V}}^{\text{2}}$ , $W/L=15$ , ${\varphi }_f=0.37\text{V}$ , and $\gamma =0.6{\text{V}}^{\text{1/2}}$ . (a) The transistor is biased at $V_{GS}=2.5\text{V}$ , $V_{SG}=3\text{V}$ , and $V_{DS}=3\text{V}$ . Determine the drain current $I_D$ . (b) Repeat part (a) for $V_{DS}=0.25\text{V}$ .