Solve

Guides

0

You visited us 0 times! Enjoying our articles? Unlock Full Access!

Question

A zener diode voltage regulator operated in the range $120 - 180 V$ produces a constant supply of $110 V$ and $250 m A$ to the load. If the maximum current is to be equally shared between the load and zener, then the values of series resistance ( $R_{S}$ ) and load resistance ( $R_{L}$ ) are:
$R_{L} = 70 Ω; R_{S} = 280 Ω$
$R_{L} = 440 Ω; R_{S} = 140 Ω$
$R_{L} = 140 Ω; R_{S} = 440 Ω$
$R_{L} = 280 Ω; R_{S} = 70 Ω$

A

R_{L} = 70 Ω; R_{S} = 280 Ω

B

R_{L} = 440 Ω; R_{S} = 140 Ω

C

R_{L} = 140 Ω; R_{S} = 440 Ω

D

R_{L} = 280 Ω; R_{S} = 70 Ω

Open in App

Solution

Verified by Toppr

The resistance offered by Zener diode will be: $R_{Z} = \frac{110}{0.25} Ω = 440 Ω$

Hence, for equal current in load and Zener diode, $R_{L} = R_{Z} = 440 Ω$

Now, total resistance will be: $\frac{440}{2} + R_{S} = R_{S} + 220$

Since current through Zener diode is $0.25 A$ , current through combination will be: $0.25 A \times 2 = 0.5 A$ .

Hence, for current to be maximum, the maximum voltage can be $180 V$ .

Therefore, $180 = 0.5 (R_{S} + 220)$

$R_{S} = 140 Ω$

Was this answer helpful?

1

Similar Questions

Q1

A zener diode voltage regulator operated in the range

120 - 180 V

produces a constant supply of

110 V

and

250 m A

to the load. If the maximum current is to be equally shared between the load and zener, then the values of series resistance (

R_{S}

) and load resistance (

R_{L}

) are:

View Solution

Q2

The figure represents a voltage regulator circuit using a Zener diode. The breakdown voltage of the Zener diode is 6V and the load resistance is

R_{L} = 4 k Ω

. The series resistance of the circuit is

R_{i} = 1 k Ω

. If the battery voltage

V_{B}

varies from

8 V

to

16 V

, what are the minimum and maximum values of the current through Zener diode ?

View Solution

Q3

A 5 V zener diode is used to regulate the voltage across load resistor

R_{L}

and the input voltage varies in between 10 V to 15 V. The load current also varies from 5 mA to 50 mA. Find the value of series resistance R.

Given,

I_{Z} (m i n) = 20 m A

View Solution

Q4

A battery

E_{A}

of

123 V

emf and internal resistance

0.4 Ω

and a battery

E_{B}

of

117 V

emf and internal resistance

0.6 Ω

supplies a current to load resistance

R_{L}

through four wires of resistors

R_{A} = 1.2 Ω, R_{B} = 1 Ω, R_{C} = 1.4 Ω

and

R_{D} = 1.4 Ω

as shown in figure. The value of load resistance for maximum load power is

View Solution

Q5

A d i o d e w h o s e i n t e r n a l r e s i s t a n c e i s

40 Ω

i s u s e d t o s u p p l y p o w e r t o a

1 k Ω

l o a d f r o m a 110 V (R M S) s o u r c e s u p p l y . T h e n t h e d c l o a d c u r r e n t w i l l b e

View Solution