Micro Proximity Sensor - 20 cm VCNL4040 (Qwiic)

Jargon buster

Plain-language definitions for the technical terms used above.

Ambient light sensor

A sensor that measures the general brightness of light falling on it, similar to how a device can adjust screen brightness automatically. It matters when you want a project to react to room lighting, daylight, shadows, or covered/uncovered conditions.

breakout

A breakout board carries a small or fine-pitched component and brings its connections out to standard, breadboard- and header-friendly pins. Describing a part as a breakout means it can be wired into a project without soldering directly to the component's tiny contacts.

Daisy chain

A wiring layout where devices are connected one after another in a line. It matters because long or awkward chains can make projects messy or less convenient, while a hub lets several devices branch out from one point.

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.

I2C address

An I2C address is the number a device uses so a microcontroller can tell it apart from other devices on the same I2C bus. It matters because two devices with the same fixed address may conflict if used together.

lux

Lux is the standard unit for measuring how much light falls on a surface, similar to how a light meter reports brightness. A sensor that outputs lux gives readings that are easier to compare between rooms, outdoor conditions, and different projects.

multiplexer

A multiplexer (mux) is a chip or circuit that selects one of several input signals and routes it to a single shared output, with select lines choosing which input is connected; running the same idea in reverse, to send one input to a chosen output, gives a demultiplexer. Multiplexers let a single controller or line work with several signals or devices that would otherwise clash on a shared connection.

Proximity sensor

A sensor that detects the presence of a nearby object without physical contact, using methods such as infrared, ultrasonic, capacitive, inductive or time-of-flight. Useful ranges vary widely between types, from a few millimetres to several metres, so check a given sensor's specified range to see whether it suits close-up touch-free triggers or longer-distance detection.

Qwiic

Qwiic is a plug-in connector system for I2C devices that uses small 4-pin cables, so you can connect compatible sensors without soldering. It matters because your controller or adapter also needs Qwiic, or you will need a cable or breakout to wire it up.