LilyPad Arduino: Wearable Electronics Getting Started

The first time I tried to integrate electronics into a costume for my daughter’s dance recital, I ended up with a rats’ nest of wires, bulky battery packs, and components that poked through the fabric uncomfortably. Then I discovered the LilyPad Arduino—and suddenly, wearable electronics went from frustrating to genuinely enjoyable. This circular, sewable microcontroller was designed from the ground up for integration into textiles, and after building dozens of e-textile projects, I can say it’s the most approachable platform for anyone wanting to merge technology with fabric.

The LilyPad Arduino represents a fundamental rethinking of how electronics can interact with clothing and soft materials. Instead of soldering wires and mounting rigid boards, you sew components together with conductive thread. The result is flexible, comfortable, and remarkably durable. Whether you’re creating light-up costumes, interactive art installations, or wearable health monitors, the LilyPad ecosystem makes it possible without a degree in electrical engineering.

What is the LilyPad Arduino?

The Arduino LilyPad is a microcontroller board specifically designed for wearable electronics and e-textile projects. Developed by Leah Buechley at MIT Media Lab in collaboration with SparkFun Electronics, the LilyPad pioneered the concept of sewable electronics—bringing programmable technology into the world of fabric, fashion, and soft goods.

Unlike traditional rectangular Arduino boards, the LilyPad features a distinctive circular design with large, flower-petal-shaped sew tabs around its perimeter. These tabs accommodate needle and thread, allowing you to stitch the board directly onto fabric and connect it to sensors, LEDs, and other components using conductive thread instead of copper wire.

The platform includes not just the main microcontroller boards, but an entire ecosystem of matching sewable components—LEDs in multiple colors, light sensors, temperature sensors, accelerometers, buzzers, buttons, and switches. Everything shares the same sewable form factor and can be connected together with simple stitching.

LilyPad Arduino Board Variants

Several LilyPad Arduino versions exist to suit different project needs:

Board	Microcontroller	I/O Pins	USB	Battery Connector	Best For
LilyPad Arduino 328 Main Board	ATmega328V	14 digital, 6 analog	Requires FTDI	None (sew tabs only)	Complex projects needing all pins
LilyPad Arduino Simple	ATmega328V	9 digital, 4 analog	Requires FTDI	JST (LiPo)	Beginners, spacious layout
LilyPad Arduino USB	ATmega32U4	9 digital, 4 analog	Built-in Micro USB	JST (LiPo)	Easy programming, no FTDI needed
LilyPad Arduino SimpleSnap	ATmega328V	9 digital, 4 analog	Requires FTDI	Built-in 110mAh LiPo	Removable/swappable projects

For beginners, the LilyPad Arduino USB offers the easiest starting experience—plug in a Micro USB cable, upload code, and go. The built-in battery charging circuit means you can power projects from a rechargeable LiPo battery and recharge simply by connecting USB.

LilyPad Arduino Technical Specifications

Understanding the LilyPad’s capabilities helps with project planning:

Specification	LilyPad 328	LilyPad USB
Microcontroller	ATmega328V	ATmega32U4
Operating Voltage	2.7-5.5V	3.3V
Clock Speed	8 MHz	8 MHz
Flash Memory	16 KB (2 KB bootloader)	32 KB (4 KB bootloader)
SRAM	1 KB	2.5 KB
EEPROM	512 bytes	1 KB
Digital I/O	14	9
PWM Outputs	6	4
Analog Inputs	6	4
Diameter	~50 mm (2″)	~50 mm (2″)
Thickness	0.8 mm (3 mm with components)	~3 mm

The 8 MHz clock speed (half of a standard Arduino Uno) conserves battery power—a critical consideration for wearables that need to run for hours on small batteries.

Essential LilyPad Components for E-Textile Projects

The LilyPad ecosystem includes a comprehensive range of sewable components:

Power Options

Component	Voltage	Rechargeable	Best For
Coin Cell Battery Holder	3V (CR2032)	No	Simple LED projects
LiPo Battery (various sizes)	3.7V	Yes	Longer-running projects
Simple Power Board	3.7V	Yes (USB charging)	Projects with 328 Main Board

Input Components

Component	Function	Connection
LilyPad Button	Momentary switch	Digital input
LilyPad Slide Switch	On/off toggle	Power control or digital
LilyPad Light Sensor	Ambient light detection	Analog input
LilyPad Temperature Sensor	Temperature measurement	Analog input
LilyPad Accelerometer	Motion/tilt detection	Analog inputs (3 axes)
LilyPad Vibe Board	Vibration motor	Digital output

Output Components

Component	Function	Colors Available
LilyPad LED	Single color light	Red, Blue, Green, Yellow, Orange, Pink, White
LilyPad Tri-Color LED	RGB color mixing	Full spectrum via PWM
LilyPad Pixel Board	Addressable RGB	Full spectrum (WS2812)
LilyPad Buzzer	Sound output	N/A

Getting Started with Conductive Thread

Conductive thread is the “wiring” of e-textile projects—stainless steel fiber spun into sewable thread that conducts electricity:

Thread Type	Resistance	Best For
2-ply thin	60-80 Ω/meter	Detailed stitching, long runs
3-ply thick	10-30 Ω/meter	Short connections, high current
Bobbin (12m)	Varies	Starter projects
Spool (360 yards)	Varies	Multiple projects

Sewing Techniques for Circuits

Every LilyPad circuit requires three elements: power source, conductive thread paths, and functional components. When sewing circuits:

1. Plan your layout before stitching—trace paths on paper to avoid crossed wires
2. Secure connections with 3-4 loops through each sew tab
3. Keep paths separate—conductive thread touching creates short circuits
4. Use running stitch between components for neat, consistent connections
5. Tie off securely and seal knots with fabric glue or clear nail polish
6. Test before finalizing—use alligator clips to verify connections work

Your First LilyPad Arduino Project

A simple light-up project teaches the fundamentals:

Materials Needed

• LilyPad Arduino USB (or Simple + FTDI)
• 3 LilyPad LEDs
• LilyPad Coin Cell Battery Holder
• CR2032 coin cell battery
• Conductive thread
• Needle
• Felt or fabric base

Basic LED Code

// Simple LilyPad LED blink

int ledPin = 5;  // LED connected to pin 5

void setup() {

  pinMode(ledPin, OUTPUT);

}

void loop() {

  digitalWrite(ledPin, HIGH);

  delay(1000);

  digitalWrite(ledPin, LOW);

  delay(1000);

}

Circuit Layout Tips

Plan LED placement so positive (+) tabs can share one conductive thread path back to a power pin, while negative (-) tabs share a path to ground. This parallel wiring ensures all LEDs receive full voltage and simplifies stitching.

Pre-Programmed LilyPad Boards

For projects without custom programming, pre-programmed boards offer plug-and-sew simplicity:

Board	Effect	Outputs
LilyTiny	4 different patterns (breathe, heartbeat, blink, twinkle)	4 tabs
LilyTwinkle	Random twinkling	4 tabs
LilyMini	Light-reactive (bright in dark, dim in light)	4 tabs

These boards are perfect for beginners or quick projects—just sew LEDs to the output tabs, add a battery holder, and switch on.

Practical LilyPad Arduino Applications

The LilyPad enables diverse creative and practical projects:

Wearable Fashion

Project Type	Components Used	Complexity
Light-up costume	LEDs, battery, switch	Beginner
Color-changing jacket	Tri-color LEDs, LilyPad USB	Intermediate
Sound-reactive dress	Microphone, Pixel boards	Advanced

Interactive Art

Project Type	Components Used
Soft sculpture	LEDs, light sensor
Responsive textile	Accelerometer, LEDs
Musical garment	Buzzer, buttons

Health and Fitness

Application	Sensors Used
Activity tracker	Accelerometer
Temperature monitor	Temperature sensor
Posture reminder	Accelerometer, vibe board

Care and Maintenance of E-Textile Projects

LilyPad projects can be surprisingly durable with proper care:

Care Aspect	Recommendation
Washing	Remove battery, hand wash with mild detergent, air dry
Storage	Store flat, avoid crushing components
Thread protection	Seal knots with fabric glue
Battery removal	Always remove before washing or storage

Never machine wash or dry LilyPad projects—the agitation and heat can damage components and break conductive thread connections.

Useful Resources for LilyPad Arduino

Official Documentation

• Arduino LilyPad Guide: arduino.cc/en/Guide/ArduinoLilyPad
• SparkFun LilyPad Learning: learn.sparkfun.com/tutorials/getting-started-with-lilypad

Tutorials and Projects

• SparkFun E-Sewing Basics: learn.sparkfun.com/tutorials/lilypad-basics-e-sewing
• LilyPad ProtoSnap Plus Activity Guide: learn.sparkfun.com/tutorials/lilypad-protosnap-plus-activity-guide

Community Resources

• Arduino Forum: forum.arduino.cc
• SparkFun Forums: forum.sparkfun.com
• Instructables E-Textiles: instructables.com/tag/type-id/category-technology/channel-wearables

Component Suppliers

• SparkFun Electronics: sparkfun.com
• Adafruit Industries: adafruit.com
• Arduino Store: store.arduino.cc

FAQs About LilyPad Arduino

Can LilyPad projects really be washed?

Yes, with important precautions. Always remove the battery before washing—this is non-negotiable. Hand wash gently with mild detergent, avoiding aggressive scrubbing over components. Rinse thoroughly and air dry completely before reinserting the battery. Machine washing and drying will damage your project. The LilyPad boards themselves are surprisingly water-tolerant once dry, but conductive thread connections can loosen if agitated too roughly. Some makers seal all connections with fabric glue or silicone for added durability in frequently washed items.

What’s the difference between LilyPad and Adafruit Flora?

Both are circular, sewable Arduino-compatible boards for e-textiles. The Flora uses an ATmega32U4 (like LilyPad USB) and operates at 3.3V. The main differences are ecosystem-related: LilyPad has been around longer with more tutorials and a larger component selection from SparkFun, while Flora integrates well with Adafruit’s NeoPixel addressable LED ecosystem. Both work excellently—choose based on which supplier’s components and tutorials appeal to you more.

How long will a coin cell battery power my project?

A CR2032 coin cell provides approximately 220mAh capacity. A single LED draws about 20mA, so theoretically 11 hours of continuous use. In practice, expect 6-8 hours with multiple LEDs. For longer runtime, use LiPo batteries—a 500mAh LiPo could run the same project for 25+ hours. Consider using sleep modes in your code and only lighting LEDs when needed to extend battery life dramatically. Motion-activated projects that sleep between interactions can run for weeks on a single battery.

Is soldering ever required for LilyPad projects?

Not for basic projects—that’s the beauty of conductive thread. However, some advanced scenarios benefit from soldering: attaching header pins for FTDI programming on boards without USB, securing connections in high-stress areas, or connecting non-LilyPad sensors. If you do solder, use lead-free solder and work carefully—the thin LilyPad PCBs can overheat. Many successful projects never require soldering at all, relying entirely on sewn connections.

Can I use regular Arduino libraries with LilyPad?

Most Arduino libraries work with LilyPad since it uses the same ATmega328 or ATmega32U4 microcontrollers as other Arduino boards. However, libraries that depend on specific pins (like hardware SPI or I2C) need verification that those pins are accessible on your LilyPad variant. Timing-sensitive libraries may behave differently due to the 8MHz clock (versus 16MHz on Arduino Uno). Always test libraries with your specific board before committing to a project design.

Final Thoughts on LilyPad Arduino

The LilyPad Arduino opened wearable electronics to creators who would never pick up a soldering iron. Its sewable design, soft construction, and thoughtful component ecosystem remove the traditional barriers between electronics and textiles. Whether you’re a fashion designer adding interactivity to garments, an educator teaching circuits through craft, or a maker building your first light-up project, the LilyPad provides an accessible path into e-textiles.

What I appreciate most about the LilyPad platform is how it respects both the electronic and textile domains. The boards are genuinely sewable—not just technically possible to sew, but designed to work naturally with needle and thread. The component ecosystem covers common needs without overwhelming beginners with choices. And the extensive tutorial resources from SparkFun and the community ensure you’re never stuck without guidance.

For anyone curious about wearable electronics, the LilyPad Arduino remains the best starting point. Pick up a starter kit, follow a simple LED project tutorial, and discover how satisfying it is to create technology you can actually wear.