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Functions of Basic Electrical Components in Electronic Circuits

Electrical components are crucial in electronic devices. They are responsible for the functioning of any electronic device. These components are often installed on a bare circuit board. A circuit board that features electronic components is an assembled circuit board. Electrical components are designed for use in electronics and electrical projects.

There are many basic electrical components available in the circuits of most peripherals. These components are the foundation of electrical and electronic circuits. Electrical circuits available in different devices share some similarities. Since there are numerous electrical components, it is necessary to really comprehend the functions and attributes of all the components.

What are Electrical Components?

Electrical components help a circuit to function. These components produce, convert, and transmit electrical energy. Examples of electrical components include resistors, diodes, transistors, and inductors. These components enable an electrical circuit to work. They are available in various shapes and sizes. Electrical components control the flow of electrons in an electrical circuit.

Electrical components feature at least two terminals which connect to the circuit. The complexity of a circuit determines the number of electrical components present in it. These components are in two different categories. These are active components and passive components.  

Active components

Active components use electrical signals to produce electric power. These components carry out their functions since they get their power through an electricity source. Also, these components need some source of energy that is gotten from a DC circuit. Active components have directionality or gain. Examples of active components include transistors, oscillator, and IC.

Passive components

Passive components can save or maintain energy in a voltage or current form. Also, these components don’t depend on a power source. Therefore, they don’t have the capability to amplify. They don’t have any directionality or gain. Examples of passive components include inductors, capacitors, resistors, and transformers.

Basic Electrical Components in a Circuit



A transformer is an electrical component that changes the levels of current and voltage in a circuit. This component has 2 coils of wire which are linked by an iron core. The transformer integrates mutual induction to transform electric energy from a circuit to another. Also, this component helps in decreasing or increasing AC voltages.

A transformer works based on the Faraday’s laws of electromagnetic induction. This law talks about the mutual inductance between two circuits connected by a magnetic flux. Transformers enable the conversion of power form a circuit to another with a different level of voltage. These basic electrical components are available in a range of sizes.


This electrical component helps to control or limit electrical current flow in a circuit. Also, it offers a particular voltage to a transistor. A resistor absorbs energy when electrical current flows through it. The energy absorbed by the resistor is usually discharged in the form of heat. This component functions based on Ohm’s law. According to Ohm’s law, voltage applied across a resistor’s terminal has a direct proportion to the electrical current that flows via it.

Resistors have variable or fixed resistances. Resistor functions when there is a need to control current flow at a desired level.  A resistor with a fixed resistance sets the appropriate conditions in a circuit. The resistance of a fixed resistor is usually determined during the design process of a circuit. In a variable resistor, there is a change in resistance based on the requirements of the electronic circuits.

Integrated Circuit (IC)

An IC is one of the most basic electrical components in a circuit. Also known as a microchip, this component has millions of transistors, capacitors, and resistors. An integrated circuit can act as a microprocessor, oscillator, and timer. This component is the foundation of several devices like computers, cell phones, and more.

An integrated circuit is widely integrated in computing devices. It can be nonlinear or linear based on its application. A linear IC has a continuous variable output. However, the level of input signal determines the output. Furthermore, linear ICs function as radio frequency and audio frequency amplifiers. A non-linear IC otherwise known as digital circuit functions at specified states. This IC is commonly used in computer networks, modems, frequency counters, and more. The logic gates are the foundation of a non-linear IC.


This semiconductor device has three terminals. It usually functions as an amplifier or a switching device. A transistor can build complex electrical systems. It comes in two major types which includes NPN and PNP. The NPN transistor is widely integrated in most circuits. The three terminals of a transistor include the collector, base, and emitter. The base of the transistor activates it while the emitter functions as the negative lead. The collector is the positive lead.

You can see a transistor as a switch that features several output states. Also, it is impossible to change these output states manually. To change the switch between different states, there is a need to run current via the transistor. You can regulate the current that passes through the transistor to regulate the output state. The main functions of a transistor include amplification, switching, and controlling electrical energy.


Active Components VS Passive Components

Battery is an electrical component that functions as a source of electric power. This component uses electrochemical cells to provide electric power. Each cell in the battery comprises an electrolyte, cathode (+), and anode (-). Batteries functions based on the electrochemical reaction principle. These components are containers that save potential and electrical energy.

Batteries convert chemical energy to electrical energy in order to provide power to several electronic devices. These components are available in  different sizes and types. There are secondary batteries and primary batteries. Primary batteries discharge their power completely before they are thrashed out. However, secondary batteries can still be used after they have discharged their power.


This two-terminal electrical component saves electrical energy in form of magnetic energy. Inductor comprises a conductor which winds in a coil. This electrical component functions according to the Inductance law by Faraday. According to this law, a current passes into its coil and from its left to right. In this case, the coil produces a magnetic field.

An inductor resists changes in a current. Inductance can be described as an inductor’s ability to generate magnetic lines. The inductance of an inductor is calculated by using this formula L= (µ.K.N2.S)/I


L represents inductance

µ represents magnetic permeability

K represents magnetic coefficient

S represents cross-section part of the coil

N represents the number of turns of the coils

Circuit breaker

Circuit breakers can be described as electrical components that prevent an electrical circuit from damaging. Overload or short circuit can cause damages to an electrical circuit. With a circuit breaker, such damages can be prevented. The main function of this electrical component is to disrupt the flow of current and detect any fault.

A circuit breaker comprises two contacts like fixed and moving contact. The fixed contact has a spring which keeps the moving contact firm after closing while the moving contact integrates stored energies to make and break the circuit. Furthermore, a circuit breaker has two different coils which are tripping and closing coil. The tripping coil trips the circuit while the closing coil closes the circuit.


This is another basic electrical component that blocks current that goes against the flow in a wire. A diode enables current to pass through one direction. This component which is made of a semiconductor material feature two different terminals which are cathode and anode. Diodes are commonly used to convert Alternating current to direct current.

These basic electrical components are made of a vacuum tube or a semiconductor material. Therefore, diodes are in two types. These are semiconductor diodes and vacuum diodes. Vacuum diodes have two electrodes which are inside a vacuum glass tube.


A fuse shares some similarities with a circuit breaker. It helps a circuit breaker to protect the electric circuit from overload. A fuse heats up and gets damaged when there is power overload. When there is an extreme current, the wire in the fuse heats up and melt. This stops the flow of current.

A fuse is available in various types. Each of this fuse is designed to sustain various amounts of currents. Therefore, a fuse features various ratings like 13A, 3A, and 5A. For example a fuse with a rating if 13A will melt at 13A. A standard fuse comprises connection, metal-fuse elements, contacts, and support body. This electrical component functions according to heating effect principle.


A motor transforms electrical energy into mechanical energy. Motors are available in appliances around us. You will find them in common appliances and even the most complex computers. These basic electrical components comprise bearings, conduit box, rotor, stator, eyebolt, and enclosure. Motors are available in different types. This includes stepper motor, AC inductance motors, and switched reluctance motor among others. Motors perform better compared to pneumatic and hydraulic alternatives.


A relay is an electromechanical switch that uses low power signal or one signal to regulate the circuits. In the past, relays function as amplifiers. However, these electrical components evolved to offer more functions in the technology sector. The basic components of relays include electrical contacts, an armature, an electromagnet, and a spring. Relays carry out logical operations on telephone exchanges and computers.

Relays integrate low currents. However, relays can also control high electric currents. Relays can either me solid state or electromechanical. They can detect irregularities that occur during power distribution.


A switch is an electrical component that breaks a current, disrupt a current and provide current from a conductor to another. This electrical component uses the on and off mechanism that performs this task. Switch are classified in four main types which are single pole sing throw, double pole single throws, double pole double throws, as well as the single pole double throws.


LED which means light emitting diode is a semiconductor device that emits light anytime there is a flow of current. This device is available on almost all appliances. You will find it on TV remote controls, hard disks, keyboards, and more. They function as status indicators in computers. This means that they help to indicate the state of current in a circuit. This light-based indicator makes it easy to check the output current or voltage.

Applications of Electrical Components

active and passive components

An electronic circuit comprises different electrical components like inductors, resistors, diodes, ICs, and more. Electrical components are integrated in various devices. Below are examples of where electrical components are integrated

Consumer electronics

A wide range of consumer electronics feature electrical components. These components are available in personal computers, printers, TVs, Refrigerators, printers, and more. Also, there are commonly used in audio and video systems like VCRs, microphones, TVs, and headphones.

Automotive devices

Electrical components are used in automotive parts, components, and systems. They are available in airbag control, window regulators, cruise control, anti-collision unit, infotainment console, and more.

Industrial electronic devices

Electronic devices used in industries feature electrical components. Biomechanics PV systems, machine learning, motor drive control, power converters, and industrial automation integrate electrical components. Without electrical components, these systems and devices won’t function.

Aerospace and defense

The application of electrical components in the aerospace and defense sector includes missile launching systems, rocket launchers, aircraft systems, and radars for military.

Medical devices

Electrical components are integrated in medical devices like respiration monitors, defibrillator device, and glucose meter among others. The use of electrical components on medical devices needs careful monitoring since they are used in saving lives.


Electrical components are designed for use in electronics and electrical projects. Electronic devices are crucial in almost all aspects of our lives. Electrical components are what makes these devices function as expected. Electronic circuit boards are the backbone of all electronic devices. These boards have electrical components attached to them. Each of these electrical components has its functions. Therefore, they all play a crucial role in the functioning of an electronic device. Electrical components feature at least two terminals which connect to the circuit. The complexity of a circuit determines the number of electrical components present in it.

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