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1. ‫بسم‬
‫ہللا‬
‫ن‬ ٰ‫الرحم‬
‫الرحیم‬
In the name of Allah who is the most gracious and merciful

2. CAPACITOR
Types of capacitors

3. Represented by
■ Khazina (009)
■ Safa (029)
■ Maham (039)
■ Eman fatima (138)

4. Capacitor
■ A capacitor is defined as a passive component which is
used for storing electrical energy.
■ A capacitor is made of two conductors that are
separated by the dielectric material. These dielectric
materials are in the form of plates which can
accumulate charges.
■ One plate is for a positive charge while the other is for
a negative charge.
■ Capacitance is the effect of the capacitor.
Capacitance is defined as the ratio of electric charge
Q to the voltage V and it is expressed as
■ C = Q/V
■ Where,
■ Q is the electric charge measured in coulombs
■ C is the capacitance measured in farad
■ V is the voltage across the plates measured in volts

5. Classification
■ According to structure, capacitors are classified as:
■ Fixed Capacitors
■ Variable Capacitors
■ Trimmer Capacitors
■ The capacitors are classified into two types according to polarization:
■ Polarized
■ Unpolarized
■ A polarized capacitor is an important electronic circuit component and is often termed an electrolytic capacitor. These
capacitors are used to achieve high capacitive density.
■ Unpolarized capacitors are preferred over polarized capacitors because it doesn’t get destroyed by reverse voltage and
can be used in pure AC circuits.
■ They also find applications in DC circuits as they don’t have positive and negative ends. The frequency of the
unpolarized capacitor is high, and the leakage current is low. After understanding the classification of capacitors, let us
learn about capacitor types.

6. Types of capacitors
■ Ceramic Capacitors
■ Film Capacitors
■ Power Film Capacitors
■ Electrolytic Capacitors
■ Paper Capacitors

7. Ceramic capacitors
■ A ceramic capacitor is considered to be one
of the most commonly used capacitors
■ The material used in this capacitor type is
dielectric. Also, ceramic capacitors are non-
polar devices which means that they can be
used in any direction in the circuit.
■ Classified into groups according to
availability:
■ Leaded disc ceramic capacitors
■ Surface mount multi-layered ceramic capacitors
■ Microwave bare lead-less disc ceramic capacitors

8. Classification depends on
temperature range
■ Depending on the temperature range, temperature drift, and
tolerance, ceramic capacitors are classified into the following
classes:
■ Class 1 ceramic capacitors: These capacitors are considered to be the most
stable capacitors with linear characteristics.
■ Class 2 ceramic capacitors: These capacitors perform better for volumetric
efficiency but their accuracy and stability are at stake. They find applications
in coupling and decoupling.
■ Class 3 ceramic capacitors: These capacitors have high volumetric efficiency
with low accuracy and low dissipation factor. They are used in decoupling.

9. Applications of ceramic capacitors
■ Ceramic capacitors are used in printed circuit boards that are used in high-
density applications.
■ Their non-polarity makes them suitable for general usage.
■ They find applications in DC motors as they are used for reducing the RF noise.
■ Ceramic capacitors are used in transmitter stations where resonant circuits
are used.

10. Film capacitor
■ Film capacitors are also known as a polymer
film, plastic film, or film dielectric.
■ The advantage of film capacitors is that they
are inexpensive and come with limitless shelf
life.
■ The film capacitor uses a thin dielectric
material with the other side of the capacitor
metalized.
■ Depending on the application, the film
capacitor is rolled into thin films. The general
voltage range of these capacitors is from 50 V
to 2 kV.

11. Types of film capacitor
■ Depending on the dielectric material used and applications, the following is
the classification of the film capacitor:
■ Heavy-duty snubber capacitors
■ SMD style capacitors
■ Axial style capacitors
■ Radial style capacitors

12. Applications of film capacitor
■ These capacitors are used as safety capacitors and in electromagnetic
interference.
■ Power film capacitors find applications in power electronics.
■ These capacitors are used for safeguarding the devices from sudden voltage
spikes.
■ Film capacitors are used for improving the power factor of the device

13. Power film capacitor
■ Construction techniques and materials that are
used in power film capacitors are similar to that
of ordinary film capacitors.
■ Polypropylene film is used as a dielectric in a
capacitor.
■ Usage of power capacitor
■ In electric power distribution, capacitor banks
are used for power-factor correction.
■ These banks are needed to counteract inductive
loading from devices like electric motors and
transmission lines, thus making the load appear
to be mostly resistive

14. Electrolytic capacitors
■ In an electrolytic capacitor metallic anode
coated with an oxidized layer used as a
dielectric. These capacitors are polarized.
Electrolytic capacitors are categorized
based on their dielectric.
■ Aluminum electrolytic capacitors –
aluminum oxide (dielectric).
■ Tantalum electrolytic capacitors –
tantalum pentoxide (dielectric).
■ Niobium electrolytic capacitors – niobium
pentoxide (dielectric).

15. Applications of electrolytic
capacitors
■ Electrolytic capacitors are used when there is a requirement for large
capacitance.
■ They are used as filtering devices that lower the ripple voltage.
■ They are used in audio amplifiers to reduce the electrical noise that is induced
by the main supply.
■ Electrolytic capacitors are used in smoothing the input and output signals in a
DC signal that has a weak AC component.

16. Paper capacitor
■ Paper capacitor is also known as a fixed
capacitor in which paper is used as the
dielectric material.
■ The amount of electric charge stored by the
paper capacitor is fixed.
■ It consists of two metallic plates, and paper,
which is used as a dielectric material, is
placed between these plates.

17. Applications of paper capacitor
■ These capacitors are used in noise filtering, coupling, and decoupling systems.
■ They are also used for blocking the DC signals so that AC signals are passed
through.
■ Sensors such as humidity sensors, fuel level sensors, etc used paper
capacitors.
■ Paper capacitors are used in audio systems of cars as they provide extra power
to the amplifiers.

18. Common capacitors
■ Capacitors are mainly divided into two mechanical groups:
■ Fixed capacitors
■ Variable capacitors
■ Some common capacitors and their names are mentioned below.
■ Ceramic capacitors
■ Aluminum, tantalum, and niobium electrolytic capacitors
■ Film and paper capacitors
■ Polymer capacitors
■ Silver mica, glass, silicon, air-gap, and vacuum capacitors
■ Double-layer capacitors
■ Pseudo capacitors
■ Hybrid capacitors

19. Values of capacitors
■ Knowing the capacitor types, and applications, let us now learn the value of
capacitor. Depending on the type of capacitor, the values of the capacitor vary.
For example, electrolytic capacitors have their values printed on their body along
with the pins. Disc capacitors have their values represented in terms of PF, uF,
KPF, etc. A black band is used to represent the negative terminal of the capacitor.
■ Therefore, the following are the ways in which capacitors values could be read:
■ The capacitance value of the capacitor is expressed in picofarads.
■ If a capacitor has the third number as zero, then the value is expressed as P.
■ If a capacitor has 3 digits, then the third number represents the number of zeros
of that capacitor. This is usually after the second number.
■ The conversion of values to KPF or uF becomes easy if the value is in PF.

22. THE END
Conclusion