LONELY BINARY 5-Set I2C 4x4 Matrix Membrane Keypad for C++ ESP32 Pico by LONELY BINARY - Used condition

LONELY BINARY 5-Set I2C 4x4 Matrix Membrane Keypad for C++ ESP32 Pico — Open-Box, 10% Off

Name: LONELY BINARY 5-Set I2C 4x4 Matrix Membrane Keypad for C++ ESP32 Pico
Brand: LONELY BINARY
SKU: awhd-us-b0g2kzw8kx
Price: 18.04 USD
Availability: InStock

Brand: LONELY BINARY

Condition: Used - Mint

$18⁰⁴

$19⁹⁹

-10% Save $1⁹⁵

Updated: 13 days ago

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Description

【5-SET SOFT KEYPAD KIT (5 KEYPADS + 5 I2C ADAPTERS)】Includes 5 flexible soft 4x4 matrix keypads (16 keys each), 5 I2C adapters to simplify connections, and a storage container — suitable for multiple projects or backups. 【SOFT MEMBRANE KEYPADS WITH EASY MOUNTING】Each keypad has a flexible design with double-sided adhesive tape on the back for attachment to project boxes, desks, or enclosures — for custom interfaces in robotics, security systems, or prototypes. 【GPIO-SAVING I2C ADAPTERS】The included adapters enable I2C communication using just 2 GPIO pins (SDA and SCL) instead of the traditional 8, freeing up pins on your microcontroller. Compatible with Raspberry Pi, ESP32, and more. 【WIDE COMPATIBILITY】Keypads and adapters support 3.3V to 5V operation for a wide range of MCUs. Easy to program with libraries like Keypad_I2C for quick setup. 【VERSATILE APPLICATIONS】Use these 4x4 keypads for numeric entry, menu navigation, or custom controls in IoT devices, home automation, smart locks, and educational projects. Soft, responsive keys provide tactile feedback in a compact form. "

Lonely Binary 5-Set I2C Soft 4x4 Matrix Keypad Kit

This bundle includes five soft membrane keypads, each with 16 keys in a 4x4 grid, along with five I2C adapters that reduce GPIO usage from 8 pins down to 2 (SDA and SCL). A storage container is included to keep components organized.

The soft keypads feature a flexible, membrane-style construction with labeled buttons (0–9, A–D, *, #). Each keypad includes double-sided adhesive backing for mounting onto project boxes, control panels, desks, or enclosures.

The included I2C adapters (based on PCF8574 chips) let you daisy-chain multiple keypads when needed. The modules support 3.3V to 5V logic levels for compatibility with platforms including UNO, Raspberry Pi 4/5, ESP32, and other microcontrollers. No soldering required for basic setups — connect via jumper wires and use libraries like Keypad_I2C.

Suitable for prototyping a smart lock, custom calculator, robotics interface, IoT dashboard, or keypad-driven menu system, for both beginner and professional applications.

Package Includes

5 × Soft 4x4 Matrix Membrane Keypads (16 keys each)
5 × I2C Adapters (PCF8574-based)
1 × Storage Container

Note:Jumper cables and microcontroller boards sold separately.

Designed in Australia

Lonely Binary is an independent Australian brand focused on open-source maker hardware.

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Product Details

SKU:: awhd-us-b0g2kzw8kx
Model:: 4x4 Matrix Keypad Kit
Country:: US
ASIN:: B0G2KZW8KX

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