Basic Electronics Components and Their Functions

About Basic Electronics Components and Their Functions, Most people use electronic devices but don’t know what is inside. 

They don’t know electronics come with essential components mostly packaged on a PCB. 

Surprisingly, you solder these components on a PCB to form a circuit that serves a specific function. 

Consequently, you’ll have usable devices like oscillators, amplifiers, and smartphones. 

Some of the basic electronic components include transistors, resistors, and capacitors. But what are their functions? 

This article looks into basic electronic components and their functions.

Table of Contents

What are Basic Circuit Components

Basic circuit components involve devices we package discreetly with more than two connecting leads. Typically, you connect these devices by soldering them on a PCB to develop a complete electronic circuit.

Consequently, they’ll help you develop usable devices like smartphones or television. 

Some basic circuit components include capacitors, inductors, switches, resistors, and fuse. 

Active and Passive Components

Passive components are those that don’t have directionality or gain. In most cases, we call the electrical components or electrical elements. Surprisingly, they will not require any external power to work. 

They employ different property control signals. All they need is a flow of current through the connected circuit. These components include transformers, diodes, and resistors. 

Active components usually rely on an external power source to modify or control signals. Unlike passive components, active components have directionality and gain. They include logic gates, transistors, and ICs.

Common Electronics Components and Functions

Now that we understand what basic electronic components are, we can now move to their functions:




A resistor, the simplest electronic component, is two terminal components that resist current flow.

Since resistors don’t have any circuit polarity, you’ll find the current flowing through them in any direction. One of its main functions is to limit the current flow, thus preventing overheating cases.

Additionally, you can use a resistor to divide your voltage into the required amount. Finally, you can use them with capacitors to develop RC filters that limit EMI and RFI interference.


capacitor image

(capacitor image)

This is an electrical component that stores charge electrostatically in an electrical field. Generally, it works as a rechargeable battery. It’s made of two conductors separated by a dielectric material.

You can use a capacitor to block direct current but let alternating current through. Additionally, you can use it to smooth your power supply’s output.

Furthermore, capacitors help stabilize power flow and voltage in transmission systems. Finally, you’ll find them in AC systems to correct the power factor.


Red diode

(Red diode)

A is a basic electrical component that lets current through in a single direction. Generally, you can use a diode to convert AC to DC power. Additionally, you can use it as a bypass diode to protect a solar panel. 

Surprisingly, a diode also helps in voltage spike protection in case of a power supply interruption. Finally, you can use a diode for signal demodulation and reverse current protection.


Power transistor

(Power transistor)

Transistors are basic electronic components with three terminals. Generally, they’re made of a base, collector, and emitter. You can use them as amplifiers or transistors in electronic circuits.

They’re perfect for switch use since they turn a small into a large current. 


This two-terminal component stores energy in the magnetic field to return it to the circuit when needed.

Surprisingly, the device has a copper coil that builds an inductance directly proportional to the turns in the coil. You can use an inductor as a filter in tuned circuits.

Additionally, they find great use in induction motors and transformers. 

Integrated Circuit (IC)

integrated circuit

(integrated circuit)

Modern electronics like smartphones and computers require complex circuits with thousands of components. And this is why ICs come into the picture.

Generally, ICs involves having many circuits on a chip. Surprisingly, they increase the device’s efficiency while reducing the manufacturing cost and size.

Even as ICs become increasingly sophisticated, their price appears to be reduced daily.


A fuse is a wire that protects a circuit from a power overload. It achieves this by melting and getting damaged by a power surge. This way, no current flows through the circuit. 

You’ll get different fuse varieties to support different current amounts. Generally, a fuse contains connections, contacts, metal fuse elements, and a support body.

The metal fuse element usually comes from copper, zinc, silver, aluminum, or alloy


A is an electrical component that you can use to disconnect or connect the electrical paths within the circuit. Generally, they allow the supply and disruption of current flow in a circuit.

When you open the contacts in a switch, it prevents current from flowing through the circuit. However, closing the contacts completes the circuit to let current through.

Common switches include mercury relay, circuit breaker, rotary, and pushbutton. 


A transformer is a device that adjusts the current levels. Generally, it has two coils linked by an iron core. Therefore, mutual induction will convert energy between the two circuits.

Surprisingly, all these happen without changing the frequency. Transformers can either be step-up or step-down transformers. For the step-up transformer, the secondary winding comes with more winding.

However, the step-down transformer has more windings on the primary coil. 

Electrical Wires & Power Cables

Electrical wires and cables are critical for connecting components to the power source. Generally, cables usually have a conductor, dielectric, and sheath. 


For any circuit to operate, you must supply it with enough power. The best power source is the battery.

Generally, it’s an electrical energy storage component that stores chemical energy but changes it to electrical energy upon demand. Generally, batteries power electronic devices like smartphones, laptops, and radios. 


This is an electromagnetic switch that opens and closes circuits electronically or electromagnetically. Surprisingly, you’ll need a very small current to close or open it.

Consequently, it’ll turn on a circuit that uses even larger power. In most cases, you’ll find them in control circuits where they regulate low currents.

However, they also find use in the regulation of high currents. Generally, you can choose between a solid-state and an electromechanical relay


This component converts electrical into mechanical energy. A motor has a rotor, enclosure, stator, conduit box, bearings, and eye box. Surprisingly, motors are more efficient than hydraulic and pneumatic systems.


How many components do you have in a circuit?

The main components of a circuit include a conductive pathway, voltage, and load.

A voltage source could be a battery and a conductive pathway by a cable. Additionally, a load could be a resistor or motor. 

How can a circuit component get damaged?

Your circuit components can fail due to excessive voltage, temperature, or mechanical shock. Also, it could result from impact or ionizing radiation. 

Can you repair circuit components?

Yes, you can remanufacture or repair a damaged circuit component. However, you need to know how to identify the problem. 


In conclusion, every electronic device comes with basic electrical components on a PCB. These components serve different functions that contribute to the device’s overall performance.

Notably, a battery supplies voltage to the circuit. Additionally, a diode current flows in a single direction. We hope you have gone through every component and understand its functionality.