Electrical Symbols & Electronic Symbols
Symbol | Component name | Meaning |
---|---|---|
Wire Symbols | ||
Electrical Wire | Conductor of electrical current | |
Connected Wires | Connected crossing | |
Not Connected Wires | Wires are not connected | |
Switch Symbols and Relay Symbols | ||
SPST Toggle Switch | Disconnects current when open | |
SPDT Toggle Switch | Selects between two connections | |
Pushbutton Switch (N.O) | Momentary switch - normally open | |
Pushbutton Switch (N.C) | Momentary switch - normally closed | |
DIP Switch | DIP switch is used for onboard configuration | |
SPST Relay | Relay open / close connection by an electromagnet | |
SPDT Relay | ||
Jumper | Close connection by jumper insertion on pins. | |
Solder Bridge | Solder to close connection | |
Ground Symbols | ||
Earth Ground | Used for zero potential reference and electrical shock protection. | |
Chassis Ground | Connected to the chassis of the circuit | |
Digital / Common Ground | ||
Resistor Symbols | ||
Resistor (IEEE) | Resistor reduces the current flow. | |
Resistor (IEC) | ||
Potentiometer (IEEE) | Adjustable resistor - has 3 terminals. | |
Potentiometer (IEC) | ||
Variable Resistor / Rheostat(IEEE) | Adjustable resistor - has 2 terminals. | |
Variable Resistor / Rheostat(IEC) | ||
Trimmer Resistor | Preset resistor | |
Thermistor | Thermal resistor - change resistance when temperature changes | |
Photoresistor / Light dependent resistor (LDR) | Photo-resistor - change resistance with light intensity change | |
Capacitor Symbols | ||
Capacitor | Capacitor is used to store electric charge. It acts as short circuit with AC and open circuit with DC. | |
Capacitor | ||
Polarized Capacitor | Electrolytic capacitor | |
Polarized Capacitor | Electrolytic capacitor | |
Variable Capacitor | Adjustable capacitance | |
Inductor / Coil Symbols | ||
Inductor | Coil / solenoid that generates magnetic field | |
Iron Core Inductor | Includes iron | |
Variable Inductor | ||
Power Supply Symbols | ||
Voltage Source | Generates constant voltage | |
Current Source | Generates constant current. | |
AC Voltage Source | AC voltage source | |
Generator | Electrical voltage is generated by mechanical rotation of the generator | |
Battery Cell | Generates constant voltage | |
Battery | Generates constant voltage | |
Controlled Voltage Source | Generates voltage as a function of voltage or current of other circuit element. | |
Controlled Current Source | Generates current as a function of voltage or current of other circuit element. | |
Meter Symbols | ||
Voltmeter | Measures voltage. Has very high resistance. Connected in parallel. | |
Ammeter | Measures electric current. Has near zero resistance. Connected serially. | |
Ohmmeter | Measures resistance | |
Wattmeter | Measures electric power | |
Lamp / Light Bulb Symbols | ||
Lamp / light bulb | Generates light when current flows through | |
Lamp / light bulb | ||
Lamp / light bulb | ||
Diode / LED Symbols | ||
Diode | Diode allows current flow in one direction only (left to right). | |
Zener Diode | Allows current flow in one direction, but also can flow in the reverse direction when above breakdown voltage | |
Schottky Diode | Schottky diode is a diode with low voltage drop | |
Varactor / Varicap Diode | Variable capacitance diode | |
Tunnel Diode | ||
Light Emitting Diode (LED) | LED emits light when current flows through | |
Photodiode | Photodiode allows current flow when exposed to light | |
Transistor Symbols | ||
NPN Bipolar Transistor | Allows current flow when high potential at base (middle) | |
PNP Bipolar Transistor | Allows current flow when low potential at base (middle) | |
Darlington Transistor | Made from 2 bipolar transistors. Has total gain of the product of each gain. | |
JFET-N Transistor | N-channel field effect transistor | |
JFET-P Transistor | P-channel field effect transistor | |
NMOS Transistor | N-channel MOSFET transistor | |
PMOS Transistor | P-channel MOSFET transistor | |
Misc. Symbols | ||
Motor | Electric motor | |
Transformer | Change AC voltage from high to low or low to high. | |
Electric bell | Rings when activated | |
Buzzer | Produce buzzing sound | |
Fuse | The fuse disconnects when current above threshold. Used to protect circuit from high currents. | |
Fuse | ||
Bus | Contains several wires. Usually for data / address. | |
Bus | ||
Bus | ||
Optocoupler / Opto-isolator | Optocoupler isolates onnection to other board | |
Loudspeaker | Converts electrical signal to sound waves | |
Microphone | Converts sound waves to electrical signal | |
Operational Amplifier | Amplify input signal | |
Schmitt Trigger | Operates with hysteresis to reduce noise. | |
Analog-to-digital converter (ADC) | Converts analog signal to digital numbers | |
Digital-to-Analog converter (DAC) | Converts digital numbers to analog signal | |
Crystal Oscillator | Used to generate precise frequency clock signal | |
Antenna Symbols | ||
Antenna / aerial | Transmits & receives radio waves | |
Antenna / aerial | ||
Dipole Antenna | Two wires simple antenna | |
Logic Gates Symbols | ||
NOT Gate (Inverter) | Outputs 1 when input is 0 | |
AND Gate | Outputs 1 when both inputs are 1. | |
NAND Gate | Outputs 0 when both inputs are 1. (NOT + AND) | |
OR Gate | Outputs 1 when any input is 1. | |
NOR Gate | Outputs 0 when any input is 1. (NOT + OR) | |
XOR Gate | Outputs 1 when inputs are different. (Exclusive OR) | |
D Flip-Flop | Stores one bit of data | |
Multiplexer / Mux 2 to 1 | Connects the output to selected input line. | |
Multiplexer / Mux 4 to 1 | ||
Demultiplexer / Demux 1 to 4 | Connects selected output to the input line. |
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Article by
EEE Department
Swarna Bharathi Institute of Science and Technology
Swarna Bharathi Institute of Science and Technology |