Chapter 3, Problem 3.51P

The transistor in the circuit in Figure P3.51 is used to turn the LED on and off. The transistor parameters are $V_{TN}=0.6\text{V}$ , ${k^{\prime }}_n=80\mu {\text{A/V}}^{\text{2}}$ , and $\lambda \text{=0}$ . The diode cut−in voltage is $V_{\gamma }=1.6\text{V}$ . Design $R_D$ and the transistor width−to−length ratio such that $I_D=12\text{mA}$ for $V_I=5\text{V}$ and $V_{DS}=0.15\text{V}$ .

Figure P3.51