LilyPad Light Sensor V2 Hookup Guide

Contributors: Gella
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The LilyPad Light Sensor is a sewable breakout board with an ALS-PT19 light sensor on it. To use the light sensor, you will need to connect to a LilyPad Arduino or other microcontroller to read the sensor values and use them in your code.

The LilyPad Light Sensor outputs voltage between 0V and 3.3V depending on the level of ambient light shining on it. As more light is applied on the sensor, more current will flow from the board through the signal tab to the microcontroller you connect the sensor to. If the sensor receives no light, no current will flow through it. In a typical indoor lighting situation, the sensor will output around 1 to 2V.

LilyPad Light Sensor

LilyPad Light Sensor


This sensor is also used on the LilyPad ProtoSnap Plus and LilyMini ProtoSnap.

LilyPad ProtoSnap Plus

LilyPad ProtoSnap Plus

LilyPad LilyMini ProtoSnap

LilyPad LilyMini ProtoSnap


To follow along with the code examples, we recommend:

Suggested Reading

To add this sensor to a project, you should be comfortable sewing with conductive thread and uploading code to a LilyPad Arduino. Here are some tutorials to review before working with this sensor:

What is a Circuit?

Every electrical project starts with a circuit. Don't know what a circuit is? We're here to help.

Serial Terminal Basics

This tutorial will show you how to communicate with your serial devices using a variety of terminal emulator applications.

LilyPad Basics: E-Sewing

Learn how to use conductive thread with LilyPad components.

Getting Started with LilyPad

An introduction to the LilyPad ecosystem - a set of sewable electronic pieces designed to help you build soft, sewable, interactive e-textile projects.