Blog » EEE Components » Passive Components » What is a capacitor?

What is a capacitor?

A capacitor is a fundamental electronic component used to store energy in an electrostatic field, making it crucial for a variety of applications in electrical circuits. In this article, we explore what is a capacitor, its structure, how it works, and its key applications, such as energy storage, filtering, and signal coupling. Their understanding is essential for designing and optimizing electronic systems.

Capacitors are passive electrical components to store electric energy.

A capacitor consists of conductive electrodes separated by an insulating layer called a dielectric. While the basic components remain the same, variations in materials, configurations, and features lead to a wide range of applications.

It stores energy in an electrostatic field created by a potential difference across the electrodes. When voltage is applied, one plate collects a positive charge, and the other collects a negative charge. The ratio of this charge to the potential difference is known as capacitance, measured in farads. The leakage current through the dielectric is called the leakage current.

Applications – What is it good for?

Capacitors are common elements in electrical circuits with several applications and different requirements, such as:

Fig.1. Typical applications overview table

Capacitor technologies

Comprehensive capacitor technologies differ in features, behavior, and range of electrical parameters covered. The most common capacitor technologies include:

 

  • Air/Vacuum
  • Aluminum
  • Ceramic
  • Film
  • Tantalum and Niobium
  • Silicon
  • Supercapacitors

 

The amazing fact about capacitors today is that they cover over 17 ranges! Of its main parameter – CAPACITANCE this is hardly achieved by any other components technology.

Fig. 2. The most common mass volume capacitor technologies capacitance vs voltage range;

source: EPCI

|

Subscribe now for our free newsletter

< Back