Electronics and Electrical Symbols

Electrical symbols are a graphical representation of basic electrical and electronic components or devices. These Symbols are used in circuit and electrical diagrams to recognize a component. It is also called a schematic symbol. Each component has typical functionality according to its operational characteristics.

An electronic circuit or schematic drawing uses a wired path between electronic components to complete the circuit. These components are represented by respective symbols for it.

Electrical and electronic symbols used in circuits are defined with various national and international standards. E.g. IEC standard, JIC standard, ANSI standard, IEEE standard, etc.,

Though electrical symbols are standardized, may vary from country to country, or engineering discipline, based on traditional conventions.

This enables anyone to read electrical circuits or schematic diagrams and floor plans with ease and clarity.

Electrical symbols virtually represent the components of electrical and electronic circuits and do not define any function or process unless the circuit is implemented with components being physically used. (E.g. the circuit on breadboard or assembled printed circuit board)

There is a symbol for each, and every electrical component or device used in a circuit such as passive components, active components, measuring instruments, logic gates etc.

A few electronic symbols that can be used in the circuit diagrams is given below for reference:

Wire Symbols

Electrical wire

Connected wires

Not Connected wires

Ground Symbols

Earth Ground

Chassis Ground

Digital/Common Ground

 

Inductor/Coil Symbols

Inductor

Iron Core Inductor

Variable Inductor

Lamp/Light Bulb Symbols

Lamp / light bulb

Lamp / light bulb

Lamp / light bulb

 

Switch and Relay Symbols

SPST Toggle Switch

SPDT Toggle Switch

Jumper

DIP Switch

Pushbutton Switch (N.C)

 Pushbutton Switch (N.O) 

SPST Relay/SPDT Relay

Solder Bridge

Resistor Symbols

Resistor (IEEE)/ Resistor (IEC)

Potentiometer (IEEE)/(IEC)

Variable Resistor / Rheostat (IEEE)/(IEC)

Trimmer Resistor

Thermistor

Photoresistor / Light-dependent resistor (LDR)

 

Capacitor symbols

Capacitor

Polarized Capacitor

Variable Capacitor

 

Antenna Symbols

Antenna / aerial

Antenna / aerial

Dipole Antenna

 

Power Supply Symbols

Voltage Source/ Current Source

Battery Cell/ Battery

Controlled voltage source/Controlled Current source

AC voltage source/Generator

 

Meter Symbols

Voltmeter/Ammeter

Ohmmeter/Wattmeter

 

Diode/LED Symbols

Diode/Zener Diode

Tunnel Diode/Light Emitting Diode

Schottky Diode/Varicap Diode

Photodiode

 

Transistor Symbols

NPN Bipolar Transistor/ PNP Bipolar Transistor

NMOS/PMOS Transistor

JFET-N Transistor/ JFET-P Transistor

Darlington Transistor

 

Miscellaneous Symbols

Motor/ Transformer

Fuse

Electric bell/Buzzer

Microphone / Loudspeaker

Op-amp /Schmitt trigger

Bus

Bus

Analog-to-Digital Converter (ADC)

Digital-to-Analog Converter (DAC)

Optocoupler

Crystal Oscillator

 

Logic Gate Symbols

AND /NAND Gate

XOR Gate / NOT Gate

OR /NOR Gate

D flip flop /Multiplexer(MUX) 2 to 1

 

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To read other interesting Electronics basics: click here

This article was first published on 18 April 2020 and was updated on 20 August 2020.