Electrical symbols and electronic circuit symbols are used to draw a schematic Picture.
| Symbol | Component | Sense |
|---|---|---|
| Wire symbols | ||
| Electrical Wiring | Conductor of electrical current | |
| Connected wires | Connected junction | |
| Wires not connected | Cables are not connected | |
| Switch symbols and relay symbols | ||
| SPST Toggle Switch | Disconnect power when open | |
| SPDT Toggle Switch | Select between two connections | |
| Button switch (NO) | Momentary switch - normally open | |
| Push Button Switch (NC) | Momentary switch - normally closed | |
| Dip switch | DIP switch is used for onboard configuration | |
| SPST Relay | Open / close relay connection by electromagnet | |
| SPDT Relay | ||
| Jumper | Close the connection by inserting a jumper across the pins. | |
| Solder Bridge | Solder to close the connection | |
| Ground symbols | ||
| Ground | Used for zero potential reference and protection against electric shock. | |
| Chassis floor | Connected to circuit chassis | |
| Digital/Common Earth | ||
| Resistor symbols | ||
| Resistor (IEEE) | Resistor reduces 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) | ||
| Shear resistor | Preset resistor | |
| Thermistor | Thermal resistance: changes resistance when temperature changes | |
| Photoresistor / light dependent resistor (LDR) | Photoresistance: changes resistance with change in light intensity | |
| Capacitor symbols | ||
| Capacitor | The capacitor is used to store electrical charge. 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 | The 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 the voltage or current of another element in the circuit. | |
| Controlled current source | Generates current as a function of the voltage or current of another element in the circuit. | |
| Meter symbols | ||
| Voltmeter | Measure voltage. It has a very high resistance. Connected in parallel. | |
| Ammeter | Measures electrical current. It has a near zero resistance. Connected in series. | |
| Ohmmeter | Measures resistance | |
| Wattmeter | Measures electrical energy | |
| Lamp / bulb symbols | ||
| Lamp / bulb | Generates light when current flows | |
| Lamp / bulb | ||
| Lamp / bulb | ||
| Diode / LED symbols | ||
| Diode | The diode allows current to flow in one direction: left (anode) to right (cathode). | |
| Zener diode | Allows current to flow in one direction, but can also flow in the reverse direction when above the breakdown voltage | |
| Schottky diode | The Schottky diode is a diode with low voltage drop. | |
| Varactor diode/varicap | Variable capacitance diode | |
| Tunnel diode | ||
| Light-emitting diode (LED) | The LED emits light when current flows | |
| Photodiode | The photodiode allows current to flow when exposed to light | |
| Transistor symbols | ||
| NPN Bipolar Transistor | Allows current to flow when there is high potential at the base (center) | |
| PNP bipolar transistor | Allows current to flow when the potential is low at the base (center) | |
| Darlington Transistor | Made from 2 bipolar transistors. It has total profit of the product of each profit. | |
| 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 | Sounds when activated | |
| Buzzer | Produces a buzzing sound | |
| Fuse | The fuse trips when the current exceeds the threshold. It is used to protect the circuit from high currents. | |
| Fuse | ||
| Bus | Contains several cables. Generally for data / address. | |
| Bus | ||
| Bus | ||
| Optocoupler / Optoisolator | The optocoupler isolates the connection to another board | |
| Loudspeaker | Converts the electrical signal into s-waveshonors | |
| Microphone | Converts sound waves into electrical signals | |
| Operational amplifier | Amplify the input signal | |
| Schmitt Trigger | Functions with hysteresis to reduce noise. | |
| Analog-to-Digital Converter (ADC) | Converts the analog signal to digital numbers | |
| Digital-to-analog converter (DAC) | Converts digital numbers to analog signal | |
| Crystal oscillator | It is used to generate a precise frequency clock signal | |
| ⎓ | Continuous stream | Continuous current is generated from a constant voltage level |
| Antenna symbols | ||
| Antenna / antenna | Transmits and receives radio waves | |
| Antenna / antenna | ||
| Dipole antennas | Simple two-wire antenna | |
| Logic Gate Symbols | ||
| NO 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. (NO + Y) | |
| OR gate | Outputs 1 when any input is 1. | |
| NOR Gate | Outputs 0 when any input is 1. (NO + O) | |
| XOR Gate | Outputs 1 when inputs are different. (Exclusive or) | |
| D Flip-Flop | Stores a bit of data | |
| Multiplexer/Mux2 to 1 | Connect the output to the selected input line. | |
| Multiplexer/Mux 4 to 1 | ||
| Demultiplexer/Demux 1 to 4 | Connect the selected output to the input line. | |
