A Zener diode of power rating 1W is to be used as a voltage regulator. If Zener diode has a breakdown voltage of 5V and it has to regulate voltage which fluctuates between 3V and 7V , what should be value of RS for safe operation

Question

A Zener diode of power rating 1W is to be used as a voltage regulator. If Zener diode has a breakdown voltage of 5V and it has to regulate voltage which fluctuates between 3V and 7V , what should be value of RS for safe operation <img class="img-fluid question-image" alt="Question" src="https://cdn.tardigrade.in/q/nta/p-ncoija9xc8uwjo7j.jpg" /> (A) 10Ω (B) 20Ω (C) 30Ω (D) 40Ω

Tardigrade Admin · Accepted Answer

P=1W Vz=5V Izmax=(P/VZ)=(1/5)A For safe operation Rs=(Vmax - VZ/IZmax)=(7 - 5/(1 / 5))=10Ω

Q. A Zener diode of power rating $1 W$ is to be used as a voltage regulator. If Zener diode has a breakdown voltage of $5 V$ and it has to regulate voltage which fluctuates between $3 V$ and $7 V$ , what should be value of $R_{S}$ for safe operation

$10Ω$

$20Ω$

$30Ω$

$40Ω$

$P = 1 W$
$V_{z} = 5 V$
$I_{z_{ma x}} = \frac{P}{V _{Z}} = \frac{1}{5} A$
For safe operation
$R_{s} = \frac{V _{ma x} - V _{Z}}{I _{Z_{ma x}}} = \frac{7 - 5}{( 1/5 )} = 10Ω$

Q. A Zener diode of power rating 1W is to be used as a voltage regulator. If Zener diode has a breakdown voltage of 5V and it has to regulate voltage which fluctuates between 3V and 7V , what should be value of RS​ for safe operation

10Ω

20Ω

30Ω

40Ω