In Figure Q2(b) Vs is an unregulated voltage that varies between 16 V and 18
V while the Zener diode voltage is VZ = 15 V. The load resistor RL can have a
value from 1000 ? to 8 (i.e., open circuit). Also you can take IZ (min) = 0 A.
(i) Find the maximum value of R1 so that the load voltage VL would be
still kept constant at 15 V for all values of RL and Vs.
(ii) Provide a symbolic expression for the maximum power dissipated by
the Zener diode.
(iii) Determine the minimum value of R1 so that the power dissipated by
the Zener diode does never exceeds 1 W for all values of RL and Vs