Diode Modeling

The power dissipation in the Zener diode is given by

P_%7B%5Ctext%7BZener%7D%7D%20%3D%20%5Cfrac%7BV_Z%5E2%7D%7BR_L%7D.

It is given that the power dissipation is 5 W and

V_Z%20%3D%2010%5C%2C%20%5Ctext%7BV%7D

. Therefore,

5%20%3D%20%5Cfrac%7B10%5E2%7D%7BR_L%7D%20%5CRightarrow%20R_L%20%3D%2020%20%5C%2C%20%5COmega.

Now, to calculate

R

, use Kirchhoff’s voltage law:

V_%7B%5Ctext%7Bin%7D%7D%20%3D%20I%20R%20%2B%20V_Z%2C

where

V_%7B%5Ctext%7Bin%7D%7D%20%3D%2035%5C%2C%20%5Ctext%7BV%7D

and

V_Z%20%3D%2010%5C%2C%20%5Ctext%7BV%7D

. The current

I

can be found using

I%20%3D%20%5Cfrac%7BV_Z%7D%7BR_L%7D%20%3D%20%5Cfrac%7B10%7D%7B20%7D%20%3D%200.5%20%5C%2C%20%5Ctext%7BA%7D.

Substituting into the equation for

R

35%20%3D%200.5%20%5Ccdot%20R%20%2B%2010%20%5CRightarrow%20R%20%3D%20%5Cfrac%7B25%7D%7B0.5%7D%20%3D%2050%20%5C%2C%20%5COmega.

Final Answer: The value of

R

50%20%5C%2C%20%5COmega

Chapter Questions
1 MCQs