Quick Learn Basic Electronic Components

Let me tell you about the basic electronic components list with images. Because we need to use them to build electronics circuits. If without learning the name and how they work.

So, the circuit designing is never complete or do not work well.

They include resistors, capacitors, diodes, transistors, LEDs, integrated circuits(ICs), etc.

Most components have two or more terminals(lead). To solder them on the circuit boards or wire connection.

This is an overview of basic electronic components. You can get in-depth information. By clicking on the link of each component.

Here are 10 Components below!

Quick learn basic electronics components

1# Resistors—resist the flow of electricity

The popularly used Resistor

Most we use the resistors to divide a voltage into a smaller voltage. This makes them very useful for reducing the current to light-emitting diodes. Which can be damaged by too much current.

Resistors are also used to divide a voltage into a smaller voltage. Resistors are used to increase the time required to charge capacitors and speed up the discharged of capacitors.

They are also used to control the gain of amplifiers.
Read more:

2# Capacitors—Store an electrical charge

3 most common capacitor types

They have many uses. Example

  • Store an electrical charge.
  • To smooth a fluctuating Signal.
  • Block continuous current while passing current pulses.

Capacitors have many types and sizes.  We often use three types of capacitors. Such as Ceramic, Mylar, and Electrolytic.

  • The Electrolytic have a lot of capacitance show on its body. Importance! Important! it is A polarised capacitor so has a positive and negative leg.
    Its negative leg (have a mark on it) must always connect to the negative terminal.
  • The Ceramic and Mylar have capacitance less than the Electrolytic.  They are really small. So, there is a code capacitor on them instead.
    Capacitor color code calculator
    For example, 104J is 0.1μF on 5% tolerance.
    Nonpolarized capacitor code


    • First and Second Digit are fixed number having unit in pF.
    • The third is Multiplier with number ten raised to the power. For example 10³.
    • Fourth is tolerance level such as J = 5%, K = 10%, M = 20%.

      How to do?

    •  What is 104k capacitor value?
      1. 10 x 10 pF. which it is 0.1μF and 10% tolerance.

Read Also

3# Diodes—one-way valves for electrical current

The diode acts as a rectifier, allowing the current to flow one way.  It must be a right way connection only.

most common diodes
Symbol and most common diodes

Diodes have different sizes and usage according to their spec. Their number will be printed on its body. As the picture below Is a diode that we use very often

4# LED—great light sources

Today, almost all the light sources. We choose to use LED. Because they are more efficient. They are low power consumption, long life, many colors.

But we should know:

  • LED is the light-emitting Diode.
  • It works when gets a forward voltage across it must exceed a threshold level (about 1.8V). and the current about 10mA up.
  • Do not use the voltage is too high, usually about 2V (depending on the type of LED). It will heat up and be damaged.
  • Must connect a correct polarity only. The LED will light up. But it is the wrong polarity (Reverse bias), it will be no current flow.
Connect LED the correct polarity

In Fig above, Look at a flat spot in the rim at the base of the LED. It will indicate the negative(-) or cathode (K). Or if new LED, short leg is always K.

5# Diodes—keep a fixed voltage across them

most common Zener diodes
Symbol and Most common Zener diodes

They have shape look likes a diode. And they also work similarly. A positive current can come to the anode to cathode easily.

But this current will not be able to flow back through the cathode to anode. Until the voltage drops across it to a set point. It will allow the current to pass.

And this voltage (VZ) drop across it will not change. For example, VZ is 5.6V.  So, We use it as a constant voltage regulator.

Read Also: Zener Diode: How to use, example circuit usage

6# Transistors—make an amplifier or switching circuit

shape of all transistors

Transistors are semiconductor devices with three leads.
A very small current or voltage at one lead can control a much larger current flowing through the other two leads.

There are many kinds of transistors. But they can be all put into two groups. One group is NPN type. I like to use it with positive voltage. The other group is PNP types. They work in the negative.

Transistors have different shapes. According to usage characteristics. Its number will be printed on its body.

Recommended: How does transistor work and uses

7# SCRs (Silicon-Controlled -rectifiers)

All shape of SCRs

The SCR is similar to a bipolar transistor. But its symbol is similar to a diode. It has three legs.

It acts as a barrier to prevent electricity from flowing through it. From the anode legs to the cathode. Until there is a control current to trigger the gate only.

But electricity cannot flow back to the cathode to Anode.

They have the symbol and shapes as follows.

Read more: How SCR works and using

7# Triac—two SCRs connected in parallel

Triac acts like an SCR but allows both direction currents to flow through it. If there is a control flow that is right.

So, They are good at AC switching controller. They have the symbol and shapes as follows.

All shape of Triac

8# Diac—like zener diode in parallel

Diac is similar to a Zener Diode. But will not allow the current to flow through both sides. Until the voltage drops across it, reaching the specified value only.

So it will allow the current to flow through and it doesn’t have any specific terminal like a resistor. There are shapes and symbols.

Symbol shape Diac

9# ICs—Integrated Circuits

IC stands for the Integrated circuit. IC is an electronic device with integrated circuits inside it. With the legs coming out to use many legs.

We need to read various functions in the manual of that device. The most common are model of the dual in the package(DIP). Look at below.

The IC has a counting pin system as follows:

Most common IC and counting pins

Look at from the top of the IC. You will see an index marker to indicate pin 1. Then we start fo count e counterclockwise 1 index point. Where the IC number of each IC is printed on the chassis as shown.

On right is a metal can model for OP-AMP IC. It is of high quality but expensive.

10# Resettable fuse or PolySwitch

Have you ever use a fuse? It protects the current and any parts from the excess current. He will sacrifice himself. Or high current blows a fuse away.

We called this component that Resettable fuse or polyswitche or multifuse or polyfuse or polyswitch. They are a passive electronic component. They are similar in function to PTC thermistors.

There are many sizes to protect against the current. Such as 0.4A 75V, 72V 500mA , etc.


PPTC Resettable Fuse PolySwitch

Cr: by uxcell
It looks like capacitors but it is a great fuse.

And see a polyswitch symbol.

Resettable fuse symbol

Cr: Image of Electronic circuit project book 1

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I always try to make Electronics Learning Easy.


      • Alan Brett-Brazill

        Hi Is the Book “Basic Electronic Components” available and from where and the cost, please.

    • Hello, Suresh badditi,
      Thanks for your visit. I am happy that you comment.
      Please tell me what do you want?


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