Description

Keypad 4×4 Self-Adhesive 16 Key – Matrix Membrane Keyboard for Arduino & Embedded Projects

The Keypad 4×4 Self-Adhesive 16 Key is a compact and versatile matrix-style membrane keypad designed for simple and reliable input control in electronic and microcontroller-based projects. With 16 tactile keys arranged in a 4×4 grid, it allows users to input numbers, letters, or commands easily — making it a must-have component for Arduino, Raspberry Pi, ESP32, and DIY electronics applications.

Its slim, flexible, and self-adhesive design makes installation quick and convenient, even in compact enclosures or project boxes. The keypad connects to your controller through a simple 8-pin interface, making it easy to integrate into a wide range of systems such as access control panels, calculators, menu-driven interfaces, and robotics.

🔋 Overview

The 4×4 Matrix Keypad features 16 keys arranged in four rows and four columns. Each key press connects a specific row to a column, creating a unique electrical signal that can be easily interpreted by a microcontroller. This matrix configuration drastically reduces the number of required I/O pins, using only 8 pins to detect all 16 keys — an efficient and space-saving design.

Each key is marked with numbers (0–9), letters (A–D), and function keys (*, #) — ideal for projects that need both numeric and character input.

The membrane structure ensures reliable tactile feedback and long operational life, while the adhesive backing allows you to mount the keypad on any flat surface for permanent or semi-permanent installation.

⚙️ Key Features

• 16-Key Matrix Layout (4×4): Includes digits 0–9, letters A–D, and function keys * and #.

• Slim & Lightweight Design: Flexible membrane construction ideal for compact projects.

• Self-Adhesive Backing: Easily sticks to flat surfaces — no need for screws or mounting holes.

• Easy Interface: Uses an 8-pin connector for direct integration with microcontrollers.

• Durable & Reliable: Designed for thousands of key presses with consistent tactile feedback.

• Water & Dust Resistant: Sealed membrane surface protects against moisture and contaminants.

• Low Power Consumption: Suitable for battery-powered or low-energy applications.

• Wide Compatibility: Works seamlessly with Arduino, Raspberry Pi, PIC, AVR, STM32, and other platforms.

🔧 Technical Specifications

🧩 Applications

The Keypad 4×4 Self-Adhesive 16 Key is perfect for a wide range of embedded, educational, and hobbyist applications, including:

• ✅ Password entry systems / Access control panels

• ✅ Arduino-based calculators or key input devices

• ✅ Menu navigation and data entry interfaces

• ✅ Home automation and IoT projects

• ✅ Robotics and mechatronics controls

• ✅ Security and alarm system input panels

• ✅ Electronic voting or selection systems

• ✅ DIY projects and educational kits

Its flexibility and simplicity make it suitable for both prototype development and long-term installations.

💡 How It Works

The 4×4 Keypad operates on a simple row-column scanning principle. Each button on the keypad connects one row line and one column line. When a key is pressed, it completes an electrical connection between a specific row and column.

Your microcontroller can then scan through the rows and columns to detect which button was pressed. Libraries such as “Keypad.h” in Arduino IDE make interfacing quick and straightforward — allowing you to identify key presses in just a few lines of code.

The keypad’s membrane layers ensure stable contacts, quick recovery after each press, and a long operational lifespan.

💪 Advantages

• Compact Design: Slim profile ideal for space-constrained projects.

• Simple Connection: Only 8 I/O pins needed for 16 keys.

• Reusable & Durable: Strong adhesive yet easy to remove when needed.

• Long Lifespan: Over 1 million keypress cycles.

• Universal Compatibility: Works with most microcontrollers and boards.

• Low Maintenance: Sealed membrane resists dust and humidity.

⚡ Usage Tips

1. Use Pull-Up or Pull-Down resistors when connecting to digital pins for stable input readings.

2. Label your wiring to match the keypad’s pinout for easier programming.

3. Use the Arduino “Keypad.h” library for easy integration and key mapping.

4. Avoid sharp bends in the flexible connector to prevent wire damage.

5. Clean the mounting surface before applying the adhesive for a strong hold.

📦 Package Includes

• 1 × Keypad 4×4 Self-Adhesive 16 Key

🌟 Summary

The Keypad 4×4 Self-Adhesive 16 Key is a practical and efficient input solution for all types of microcontroller-based systems. It offers a combination of ease of use, compact design, and reliable performance, making it ideal for both beginners and advanced developers.

Whether you’re creating a password-protected lock, a calculator, or an interactive menu system, this keypad delivers excellent tactile feedback and seamless integration with your electronic projects. With its self-adhesive design, flexible cable, and durable build, it’s the perfect choice for any DIY or professional embedded project.