A diode has Zener voltage of 10 V and maximum power dissipation of 0.5 W, then the minimum resistance to be used in series with this diode for safety when it is connected to a 25 V power supply is Ω.
Answer
300
Solution
Maximum safe current through the diode:
Imax= PmaxVZ= 0.510=0.05 A
Voltage across the series resistor =25-10=15 V
Rmin= 15Imax= 150.05=300
Answer: 300