Question:
A Zener of power rating 1 W is to be used as a voltage regulator. If Zener has a breakdown of 5V and it has to regulate voltage which fluctuated between 3V and 7V, what should be the value of Rs for safe operation in the figure?
Solution:
Power = 1W
Zener breakdown voltage = 5V
Minimum voltage = 3V
Maximum voltage = 7V
P = VI = 0.2A
Rs = 10 Ohms.