This document summarizes different types of capacitors. It discusses ceramic capacitors, film capacitors, electrolytic capacitors, supercapacitors, variable capacitors, and trimming capacitors. Ceramic capacitors use ceramic material as the dielectric and come in different classes with varying accuracy and stability. Film capacitors use plastic film as the dielectric and come in metal foil or metallized film varieties. Electrolytic capacitors have a high capacitance-voltage product and use an oxide layer as the dielectric. Variable and trimming capacitors allow changing the capacitance through mechanical adjustment. Supercapacitors bridge the gap between electrolytic capacitors and batteries with lower voltage but higher capacity.

1. Types of Capacitors
Presentation By:
1. Pranesh Kulkarni
Electronic Circuits

2. CAPACITORS
A capacitor is a device that stores electrical energy in an electric field. It is
a passive electronic component with two terminals.
Capacitors are manufactured in many forms, styles, lengths, girths, and
from many materials. They all contain at least two electrical conductors
separated by an insulating layer called the dielectric.
Non polarised Capacitors :
Ceremic Capacitors
Film Capacitors
Polarised Capacitors :
Supercapacitors
Electrolytic Capacitors

3. Supercapacitors
Also called an ultracapacitor, is a high-capacity capacitor but with
lower voltage limits, that bridges the gap between electrolytic
capacitors and rechargeable batteries.
Consist of two electrodes separated by an ion-permeable membrane
(separator), and an electrolyte ionically connecting both electrodes.
Based on the design of the electrodes Supercapacitors are divided
into three families:
Double-layer capacitors: with carbon electrodes
 Pseudocapacitors - with electrodes out of metal oxides
Hybrid capacitors

4. Applications :
1. Consumer electronics.
2. Grid power and Low power equipment buffer.
3. Voltage stabilizer.
4. Energy Harvesting Systems.
5. Incorporation into batteries.
6. Street Lights.

5. VARIABLE CAPACITOR
A variable capacitor is a capacitor whose capacitance may be
intentionally and repeatedly changed mechanically or electronically.
Capacitance values vary between 10 to 500pF.
Tunning Capacitors:
Contains a stator, a rotor, a frame to support the stator and a mica capacitor.
Generally have capacitance values from few Pico Farads to few tens of Pico
Farads.
 Used in LC circuits in radio recievers.

6. Trimming Capacitors:
Usually fixed in such a place where there is no need to change the value of
capacitance
There are three leads of a trimmer capacitor, one connected to stationary
plate, one to rotary and the other one is common. The movable disc is a semi-
circular shaped one
The Trimmer Capacitors are easily fixed on a PCB (Printed Circuit Board) and
they are mostly used for calibration of equipment.
Uses:
Utilized to set frequency of resonance in LC circuits.
To adjust the radio for impedance matching in antenna tuner devices.

7. Ceremic Capacitors
A ceramic capacitor typically referred to as "Disc Capacitors" is a non-
polarized fixed capacitor made out of two or more alternating layers
of ceramic and metal in which the ceramic material acts as the
dielectric and the metal acts as the electrodes.
The ceramic material is a mixture of finely ground granules of
paraelectric or ferroelectric materials
Values ranging from a few picofarads to one or two microfarads but
their voltage ratings are generally quite low.
It tends to display substantial non-linear changes in capacitance
against temperature.

8. Classes of ceremic capacitors:
Class 1 ceramic capacitors
Offers high stability and low losses.
These are accurate, temperature-compensating capacitors.
especially suited for resonant circuit applications.
Class 2 ceramic capacitors
have a dielectric with a high permittivity
lower accuracy and stability.
Suitable for bypass, coupling and decoupling applications.
Class 3 ceramic capacitors:
 have very high permittivity, up to 50,000 and
lower accuracy and stability.
have very high losses and age over time.

9. Film capacitors
Film capacitors or plastic film capacitors are non-polarized capacitors
with an insulating plastic film as the dielectric. The dielectric films are
drawn to a thin layer, provided with metallic electrodes and wound
into a cylindrical winding.
Film type capacitor are available in ranges starting from 5pF to 100uF.
Made out of two pieces of plastic film covered with metallic
electrodes, wound into a cylindrical shaped winding, with terminals
attached, and then encapsulated.
Metallized film capacitors offer self-healing properties.
Dielectric breakdowns or shorts between the electrodes do not
destroy the component.

10. There are two different types of plastic film capacitors:
Film/foil capacitors or metal foil capacitors
made with two plastic films as the dielectric.
 Metallized film capacitors
made of two metallized films with plastic film as the dielectric.
Used for oscillators and resonant circuits for electronic filter
applications
Traditional inductive ballast used in fluorescent lamps.
Safety and EMI/RFI suppression film capacitors
High peak current operation required for protection against transient
voltages.

11. Electrolytic Capacitors
An electrolytic capacitor is a polarized capacitor whose anode or
positive plate is made of a metal that forms an insulating oxide layer
through anodization.
Electrolytic capacitors have a much higher capacitance-voltage
product per unit volume.
Suitable for passing or bypassing low-frequency signals, and for
storing large amounts of energy.
They are widely used for decoupling or noise filtering in power
supplies
The large capacitance per unit volume

12. Aluminum electrolytic capacitors
It use a high-purity etched aluminium foil with aluminium oxide as dielectric
Higher energy density and Higher power density
Limited lifetime due to evaporation
Relatively poor ESR and Z behavior at very low temperatures
Tantalum electrolytic capacitors
It uses a sintered pellet of high-purity tantalum powder with tantalum pentoxide as
dielectric
Consists of a pellet of porous tantalum metal as an anode surrounded by liquid or
solid electrolyte as a cathode
A niobium electrolytic capacitor
Polarized capacitor whose anode electrode (+) is made of passivated niobium metal
on which an insulating niobium pentoxide layer acts as the dielectric of the niobium
capacitor.
Suitable for all portable electronic systems with flat design
Available with solid electrolyte for low ESR applications and stable electrical
parameters.

13.  Electrolytic capacitors for special applications include motor start
capacitors, flashlight capacitors and audio frequency capacitors.

14. THANK YOU