Question $4(25$ marks$)$

Refer to the circuit shown in Figure $4,$ apply the constant voltage drop model for all diodes.

Figure $4,-2V$

a$)$ State the operating states, i$.$e$.,$ ON$/$OFF for each diode.

$(4$ marks $)$

b$)$ Re$-$draw the circuit by replacing each diode with its equivalent circuit. $(8$ marks $)$

c$)$ Calculate the values of current $I_1,I_2,I_3$ and $V_o.$

$(8$ marks $)$

d$)$ Calculate the power dissipation $(P{D}_D)$ of $D_4.$

$(5$ marks $)$