Zener Diodes

Question 1

What is a zener diode?

Answer 1

A special kind of diode that allows current through in forward direction AND reverse direction, at a certain voltage

Question 2

Draw a typical graph for a zener diode

Answer 2

Flat line from Vout until it reaches iMAX, at which point it decreases gradually

Question 3

What is the equation for the resistance in the series resistor?

Answer 3

R = __Vrz__
iMAX

Vrz is the sum of currents entering from both ends of resistor: watch out for which way the zener diode sends its voltage round

Question 4

What is the equation for power in the resistor in a zener circuit?

Answer 4

P = i^2 x R

Question 5

What is the equation for power of the zener diode?

Answer 5

P = Vz x iMAX

Voltage of zener) x (max current

Question 6

What is the equation for minimum resistance of a load resistor in a zener circuit?

Answer 6

RLmin = __Vz__

iMAX

Question 7

What is the advantage of using a Zener diode to combat voltage droop?

Answer 7

Simple, 1 component circuit

Question 8

What is the disadvantage of a Zener diode?

Answer 8

Even with no load in RL, still uses max current from voltage source