-Refer to the figure above. If the zener had a voltage rating of 3.7 V, Vout would be
A)20.2 V.
B)25 V.
C)18.2 V.
D)7.1 V.

Question

-Refer to the figure above. If the zener had a voltage rating of 3.7 V, Vout would be
A)20.2 V. 
B)25 V. 
C)18.2 V. 
D)7.1 V.

Quizplus · Accepted Answer

The zener diode will conduct when the voltage across it reaches its zener voltage, which is 3.7 V. When this happens, the zener diode will clamp the voltage across it to 3.7 V. The voltage across the resistor will be the difference between the input voltage and the zener voltage, which is 25 V - 3.7 V = 21.3 V. The current through the resistor will be 21.3 V / 1 kΩ = 21.3 mA. The voltage across the output capacitor will be the same as the voltage across the resistor, which is 21.3 V.

-Refer to the Figure Above