Intro to Capacitors

Introduction

~ Have u ever wondered how spurious electric signals are filtered, or how noise is reduced in digital circuits, electricity circuits, electricity supply units, etc.

Well Today I'm gonna clear your doubts and answer your questions using 1 word, capacitors, they are one the most important components in any electric circuit. Their primary function is to store electrostatic energy in an electric powered subject and provide this power to the circuit when necessary. Capacitors enable AC to bypass, but however block DC to avoid hazardous breakdown of the circuit thus preventing damage of sensitive components in an electrical circuit.

What is a Capacitor ? 

- A capacitor is a two-terminal passive electrical component that stores electrical energy.
- The capacitor stores electrical energy in the form of an electric field.
- A quick way of remembering the capacitor is thinking of it as a bucket that stores electrical energy.
- Capacitance is an electrical phenomenon whereby electric charge is stored.
- The Standard International (SI) Unit for capacitance is the Farad, but the capacitance of a capacitor ranges from picofarad to Milli farad.
1 Farad = 1 Coulomb.

The capacitance of a capacitor is its ability to store electrical energy, some capacitors have a higher capacitance than others.

Capacitors are widely used in electronic circuits. Capacitors are used in AC circuits to block DC current, it is also used as a filter like a tuning device. A resistor combines in a series with a capacitor form a timing circuit.

                   Types of Capacitors

- There are 2 main types of capacitors namely :
a) Polarized Capacitors
b) Non-polarized Capacitors

• Polarized capacitor had to be connected correctly in a circuit with a positive leg connected to the higher potential in the circuit and the negative leg to the lower potential in the circuit.

            Practical forms of capacitors

Electrolytic
• Generally, they are polarized capacitors, they contain an electrolyte as a dialectic.
• They fall into a category, 1 Aluminum capacitor, Tantalum Capacitor, Niobium Capacitor etc.

Ceramic
• Ceramic capacitors has a ceramic as a dielectric.
• Usually it is a mixture of ceramic and titanium dioxide.
• Some ceramic capacitor are mixed with barium titanate.

Air capacitor
• Ceramic capacitors has a ceramic as a dielectric.
• Usually it is a mixture of ceramic and titanium dioxide.
• Some ceramic capacitor are mixed with barium titanate.

Paper capacitor
• These has a thin paper as a dielectric of relative permittivity about 5 between the plates of the capacitor.
• The paper is rolled into a cylinder.

Fixed capacitor