Component Reference Library

A Light Emitting Diode — a tiny light that only lets current flow in one direction.

A component that resists the flow of electricity, limiting current in a circuit.

A tactile switch that connects two pins when pressed and disconnects them when released.

A variable resistor with a knob. Turning the knob changes resistance between 0 and its max value.

A small motor that rotates to a precise angle (0–180°) based on a PWM signal.

Light Dependent Resistor — resistance changes based on light intensity. Bright = low resistance, dark = high resistance.

A small speaker that makes tones when given a PWM signal. Perfect for beeps, alarms, and simple melodies.

Measures distance by sending an ultrasonic pulse and timing the echo. Range: ~2cm to 400cm.

A single LED with three separate dies (red, green, blue) in one package. Mix colors by changing the brightness of each channel.

A 16-character × 2-line character display. Shows text and numbers.

A digital sensor that measures temperature (0–50°C) and relative humidity (20–90% RH).

A sensor that detects infrared light pulses from TV remotes and other IR transmitters.

An electrically-operated switch. A small Arduino signal switches a separate high-power circuit on or off.

A motor that rotates in precise steps, allowing exact position control without feedback.

A component that stores and releases electrical charge. Used for filtering noise and stabilizing power.

A three-pin semiconductor that uses a small base current to switch or amplify a larger collector current.

A one-way valve for electricity. Current flows from anode (+) to cathode (−) but not the other direction.

A DC motor spins continuously when powered. The L298N driver lets you control speed and direction from an Arduino without frying it.

A crisp 128×64 pixel black-and-white display that connects via I2C using just two wires.

A Bluetooth 2.0 serial module that lets your Arduino communicate wirelessly with a phone or PC.

Reads and writes 13.56 MHz RFID cards and key fobs. Used for access control, identification, and tagging.

Two probes measure the resistance of soil. Wet soil conducts better, so a lower resistance means more moisture.

A 6-axis IMU that measures acceleration on X/Y/Z axes and rotation rate on X/Y/Z axes, all over I2C.

An addressable RGB LED strip where each LED has its own controller chip. Control thousands of LEDs with a single Arduino pin.

A two-axis analog joystick with a built-in click button. Outputs X and Y voltages plus a digital select signal.

A display with 7 LED segments arranged to show digits 0–9 and some letters.

A 16-button keypad (4 rows × 4 columns) that uses only 8 Arduino pins via matrix scanning.

Lets your Arduino read and write files on a standard micro SD card over SPI.

A battery-backed clock module that keeps accurate time (±2 ppm) even when your Arduino is powered off.

Detects combustible gases (LPG, propane, methane) and smoke. Useful for safety and air quality projects.