Adafruit ItsyBitsy ESP32 w.FL Antenna - 8 MB Flash / 2 MB PSRAM

Jargon buster

Plain-language definitions for the technical terms used above.

3.3V regulator

A 3.3V regulator is a power circuit that provides a steady 3.3 volts for parts that need that supply voltage. On a breakout board, it can let the sensor run safely even when the connected microcontroller or power source uses a higher voltage.

BLE

BLE stands for Bluetooth Low Energy, a Bluetooth mode designed for low power use and broad compatibility with modern phones and computers. It connects well to battery-powered and mobile devices, including Apple hardware, though it behaves differently from Bluetooth Classic and its serial-style profiles.

Bootloader

Small starter software on a microcontroller that lets new code be uploaded before the main program runs. Knowing how to enter bootloader mode matters when you need to program the board or recover it after a faulty sketch.

CircuitPython

A beginner-friendly version of Python designed to run directly on microcontroller boards. If a product supports CircuitPython, you can often program it by copying code files onto the board rather than setting up a more complex toolchain.

DAC

A digital-to-analogue converter turns numbers from the microcontroller into a real analogue voltage. It matters if you want to generate simple waveforms, audio-style signals, or variable control voltages rather than just on/off outputs.

deep sleep

Deep sleep is a low-power mode where the microcontroller turns off most functions while keeping just enough circuitry active to wake up later. It is important for battery-powered projects because it can greatly extend how long the device runs between charges.

ESP32

ESP32 is a family of low-cost microcontroller chips and modules from Espressif with built-in WiFi and Bluetooth. They support programmable firmware and over-the-air updates, and are commonly programmed with toolchains such as the Arduino core and ESP-IDF.

GPIO

General-purpose input/output pins are microcontroller pins you can set in software to read signals, switch devices on and off, or connect to peripherals. The number of GPIO pins matters because it limits how many buttons, LEDs, sensors, and other parts you can wire directly to the board.

Headers

Rows of connector contacts on a fixed pitch (commonly 2.54 mm) used to link a board to a breadboard, jumper wires, or another board. They come as male pin headers and female socket headers; when a module ships with pre-soldered headers it can be used straight away, whereas bare pads require soldering the pins yourself.

I2C

I2C is a two-wire communication bus used by many sensors and small modules. It matters because several I2C devices can share the same two wires, but each device needs a compatible address and your controller must support I2C.

I2S

I2S is a digital audio interface used to send sound data between chips, such as from a microcontroller to an audio amplifier or DAC. It matters if your project needs cleaner digital audio output than a basic buzzer or PWM signal can provide.

IDE

Short for Integrated Development Environment, a program used to write, run and manage code. It matters because some learners prefer a traditional coding workspace instead of a guided notebook-style lesson.

IoT

Short for Internet of Things, meaning physical devices that connect to networks or the internet to send data or be controlled remotely. It matters if you want projects such as connected sensors, remote controls or classroom data-logging activities.

LED

A light-emitting diode (LED) is a small electronic component that emits light when current flows through it in the correct direction. Because it only conducts one way, its polarity matters, and a through-hole LED must be soldered the correct way around to light up.

Light sleep

A low-power mode where the microcontroller pauses much of its work but can wake up faster than from deep sleep. It matters for battery projects because it reduces power use while still allowing the board to respond reasonably quickly.

microcontroller

A microcontroller is a small computer on a single chip that runs a stored program and controls connected inputs and outputs such as buttons, sensors, displays and communication interfaces. In a device built around one, it is the part that executes the code and coordinates the device's behaviour.

MicroPython

A version of the Python programming language made to run on microcontrollers. It matters because it lets beginners write readable code to control LEDs, sensors, motors and displays without needing to start with lower-level languages.

NeoPixel

A type of addressable LED system where colour data is sent along a single digital data line from one LED or controller to the next. Compatibility matters because the timing and signal format must match for the lights or driver board to respond correctly.

PCB

A printed circuit board (PCB) is a board, usually rigid, with etched copper tracks that connect electronic components together without loose wiring. Components are mounted on the board and signals route between them through the copper layout.

PWM

Pulse Width Modulation is a way for a digital pin to simulate variable output power by switching on and off very quickly. It matters for controlling things like LED brightness, motor speed, or servo-style signals from a microcontroller pin.

Quiescent power

The small amount of power a circuit uses when it is idle rather than actively doing work. It matters for battery-powered projects because even tiny standby power use can drain a battery over time.

RF

RF means radio frequency, referring to signals used for wireless communication and other high-frequency electronics. A low-noise, stable power supply is important for RF circuits because power noise can affect signal quality and measurements.

RGB

Short for red, green and blue, the three primary colours of light that are mixed in varying amounts to make a wide range of colours. In electronics RGB can refer to an LED or pixel that blends these three colours, or to a colour signal or interface that carries separate red, green and blue channels.

SCL

The clock line used by the I2C bus to keep data transfers timed between a controller and connected devices. When wiring I2C, SCL must be connected to the SCL pin on every device sharing the bus.

SDA

The data line used by the I2C bus to carry information between a controller and connected devices. When wiring I2C, SDA must be connected to the SDA pin on every device sharing the bus.

SPI

A fast serial communication bus often used for displays, memory cards, and sensors. It matters because SPI devices need specific pins for clock and data, plus a separate chip-select line for each device.

STEMMA

A plug-and-cable connection system used on some maker electronics boards to make wiring simpler. If a product uses STEMMA, you need the matching cable or connector type to plug it in without soldering.

STEMMA QT

A small plug-in connector system for I2C boards that lets you connect compatible sensors and controllers without soldering. It matters because it can make wiring faster and less error-prone, especially when adding several small modules to a project.

u.FL

u.FL is a tiny snap-on antenna connector often used on compact wireless boards. A board with u.FL usually needs an external antenna, which matters if the product will be inside an enclosure or needs better antenna placement.

UART

UART is a simple asynchronous serial interface that sends data over separate transmit and receive wires, usually labelled TX and RX, with both ends set to the same baud rate. It is a common way for microcontrollers and other serial devices to exchange data.

USB to serial converter

A chip that converts a USB connection into the serial (UART) signals a microcontroller understands. A board that includes one usually appears to a computer as a serial port for programming and debugging, rather than as a native USB device such as a keyboard or mass-storage drive.

w.FL

A very small radio-frequency antenna connector used on compact wireless boards. It matters because you need a matching w.FL antenna or adapter before the board can use an external antenna.