This document outlines information about a Zener diode, voltage doubler, and half wave rectifier. It includes circuit diagrams and data tables for each component. The Zener diode section explains that it allows current to flow backwards at a breakdown voltage and is used to limit voltage increase. The voltage doubler charges capacitors to produce twice the input voltage at the output. The half wave rectifier only allows one half of the AC cycle to pass while blocking the other half, producing lower DC output with higher ripple. Applications are listed for each component.

1. University of halabja
college of science
physics department
3rd stage
{Electronic lab}
Propertied by:
shene Aziz

2. Outline
• Zener diode
• Voltage doubler
• Half wave rectifier

3. What is Zener diode
Zener diode is a special type of diode designed to reliably allow current to flow
"backwards" when a certain set reverse voltage, known as the Zener voltage, is
reached. Zener diodes are manufactured with a great variety of Zener voltages and
some are even variable. Some Zener diodes have a sharp, highly doped p–n junction
with a low Zener voltage, in which case the reverse conduction occurs due to
electron quantum.

4. Why is the Zener diode used in reverse bias?
1. It behaves like a normal diode in forwarding bias.
2. When the Zener diode is reverse biased the junction potential increases.
3. When the diode's breakdown voltage VZ is reached at which point a process
called avalanche breakdown occurs in the depletion layer of the semiconductor.
4. The Zener Diode is used in its “reverse bias”.
5. Current starts to flow through the diode to limit this increase in voltage.
6. Zener diode is a highly doped diode.

5. Circuit Zener diode

6. Data and graph Zener diode
v(d) v(s) I(mA)
5.1 5 0.005
8.5 8.8 0.08
9.1 11 16.6
9.1V

7. Application Zener diode
1.As a voltage regulator
2. Protects from overvoltage
3. Used in clipping circuits
4. Used to shift voltage

8. What is voltage doubler
A voltage doubler is an electronic circuit which charges capacitors from the input
voltage and switches these charges in such a way that, in the ideal case, exactly
twice the voltage is produced at the output as at its input

9. Circuit voltage doubler

10. Data and graph voltage doubler
Input Ac
voltage(v)
V Peak(v) Out put
voltage(v
)
3 4.5 8
6 8 17
9 12 36

11. Application voltage doubler
1. Ion pumps
2. Television CRT
3. X-Ray systems
4. Copy machine
5. Radar equipment

12. What is half wave rectifier
Half-wave rectifiers transform AC voltage to DC voltage. A halfwave rectifier
circuit uses only one diode for the transformation. A halfwave rectifier is defined
as a type of rectifier that allows only one-half cycle of an AC voltage waveform to
pass while blocking the other half cycle. In this session, let us know in detail about
the half-wave rectifier

13. Circuit half wave rectifier

14. Graph half wave rectifier

15. Result calculation half wave rectifier
• Vm=Vi-Vd
• VRms=
𝑉𝑚
2
• Vavg=
𝑉𝑚
𝜋
• lRMS=
𝑉𝑅𝑚𝑠
𝑅
• Iavg=
𝐼𝑚
𝜋
• E=
𝑃(𝑑𝑐)
𝑃(𝑎𝑐)
• Ripple factor=
𝐼(𝑅𝑚𝑠)
𝐼(𝑎𝑣𝑔)

16. Disadvantage half wave rectifier
• Converts only one cycle of the sinusoidal input given to it and the other cycle
gets wasted. Thus, giving more power loss.
• HWR produces lower output voltage.
• The output current thus obtained is not purely DC and it still contains a lot of
ripple ( has a high ripple factor).

17. Advantage half wave rectifier
• Simple circuit with less number of components
• Economical at initial state. Although there is a higher cost over time due to more
power losses

18. Application half wave rectifier
• Soldering
• AM radio
• Pulse generated circuits
• Single demodulation
• Voltage multiplier