Capacitor Types

What is a Capacitor and Different Types of Capacitors? 

The capacitor is a device that has the ability or "power" to store energy in the form of an electrical charge that creates a potential difference (Static Voltage) through its plates, much like a small rechargeable battery. There are many types of capacitors available from very small capacitor beads that use resonance circuits to large power factor correction capacitors, but they all do the same, they store charge. In other words, the capacitor is an electronic component whose function is to store electrical charges. It is made of two conductors separated by a dielectric film. These plates accumulate electrical charges when connected to a power source. 

They are often storage sites for analogue signals and digital data. In general, comparisons between the different types of capacitors are made with respect to the dielectric used between the plates. Some capacitors look like tubes, small capacitors are often made from ceramic materials and then dipped into an epoxy resin to seal them. Below are some of the more common types of capacitors available.


Capacitor Types 

The types of capacitors available range from very small, delicate trimming capacitors used in oscillators or radio circuits, to large-scale metal-type capacitors used in high-voltage power correction and smoothing circuits. 

The comparison between the different types of the capacitors are generally made with respect to the dielectric used between the plates. Unlike resistors, there are also various types of capacitors that allow us to vary their capacitance value for use in radio or "frequency tuning" style circuits. 

Some of the capacitors appear like tubes since the metal foil plates are rolled up into a circle to make a small bundle with the insulating dielectric layer sandwiched between them.

Small capacitors are often made from ceramic materials and then immersed in epoxy resins to seal them. Either way, the capacitors play an important role in electronic circuits, so here are some of the more "common" types of capacitors available.


Applications of Capacitors

Capacitors have been used in both physical and electronic devices. They are used in filter applications, energy storage systems, engine starters, and signal processing equipment.


Four Types of Capacitors

1. Film Capacitors -

Film capacitors are the most widely prepared of a variety of types of capacitors, consisting of a relatively expansive category of capacitors defining their dielectric properties. They are available in almost any weight and voltages up to 1500 volts. They vary in any tolerance from 10% to 0.01%. In addition, film capacitors come in a variety of shapes and case types. There are two types of film capacitors, the type of radial lead and the type of axial lead. The film capacitor electrodes may be metallic aluminium or zinc, mounted on one or both sides of the plastic film, resulting in metallic film capacitors called film capacitors. The film capacitor is shown in the following figure:

2. Ceramic Capacitors:

Ceramic capacitors are used in high-frequency circuits such as RF audio. They are also the best alternative for high-frequency compensation for audio circuits. These capacitors are also called disk capacitors. Ceramic capacitors are made by coating two sides of a small silver porcelain or ceramic disk and then stacked together to make a capacitor. Low capacitance and high capacitance in ceramic capacitors can be achieved by changing the thickness of the ceramic disk used..

3. Electrolytic Capacitors:

These are the most widely used capacitors with a wide tolerance capacity. Electrolytic capacitors are obtainable with working voltages of up to 500V, although high capacitance values are not accessible at high voltage and higher temperature units are not normal. Two types of electrolytic capacitors, Tantalum, and Aluminum are common. Electrolytic capacitors are categorized based on their dielectric.

  • Aluminium electrolytic capacitors – aluminium oxide ( dielectric).

  • Tantalum electrolytic capacitors – tantalum pentoxide (dielectric).

  • Niobium electrolytic capacitors – niobium pentoxide ( dielectric).

4. Variable Capacitors: 

Among the different types of capacitors are a Variable Capacitor, it is one whose capacity can be changed mechanically intentionally and repeatedly. This type of capacitor was used to set the resonance frequency in LC circuits, e.g. to adjust the radio for impedance matching in antenna tuner devices.


What are Common Capacitors?

Capacitors are mainly divided into two mechanical groups:

  • Fixed capacitors

  • Variable capacitors


Capacitor Types and Uses

Some Common Capacitors and Their Names are Mentioned in the Table Below.

Ceramic capacitors

Aluminium, tantalum, and niobium electrolytic capacitors

Film and paper capacitors

Polymer capacitors

Silver mica, glass, silicon, air-gap, and vacuum capacitors

Double-layer capacitors

Pseudocapacitors

Hybrid capacitors


The easiest design of the capacitor is the use of two parallel metal plates separated by an insulation layer called a dielectric.

FAQ (Frequently Asked Questions)

1. What is a Capacitor in Physics?

Capacitor is one of the most commonly used components in the design of electronic circuits. It plays an important role in a number of embedded applications. It's available for various scores. It consists of two metal plates which are separated by a non-conductive or dielectric layer.

As per capacitor definition in electronics, Capacitors are energy storage devices that have the ability to store electrical charges across their plates. As a result, the capacitors store energy due to their ability to store charge, and the ideal capacitor would not lose its stored energy.

2. What is the Main Function of a Capacitor?

The main functions of Capacitors are - 

  • The capacitor consists of two metal plates separated by a dielectric one.

  • The dielectric can be made from many insulating materials such as air, glass, paper, plastic, etc.

  • The capacitor is capable of holding electrical charges and electricity.

  • The higher the value of the capacitance, the higher the charge the capacitor will store.

  • The larger the area of the plates or the smaller their separation, the more load the capacitor can carry.

  • The capacitor is said to be "fully charged" when the voltage across its plates is equal to the supply voltage.

  • The electrical charge symbol is Q and its unit is Coulomb.

  • Electrolytic capacitors shall be polarized. They've got a + ve and a-ve terminal.