4x4 Matrix Membrane Keypad

Punch in your secret key into this numeric matrix keypad. This keypad has 16 buttons, arranged in a telephone-line 3x4 grid + 4 extra keys - A, B, C and D. It's made of a thin, flexible membrane material with an adhesive backing (just remove the paper) so you can attach it to nearly anything. The keys are connected into a matrix, so you only need 8 microcontroller pins (4-columns and 4-rows) to scan through the pad.

Check the resources at bottom of this description to get the tutorial and sample code for Arduino.

Note: You might need extra long header pin or jumper wires so you can plug this into a breadboard or Arduino with ease. Check this video by Gadget Reboot:

• 4x4 bendable membrane keypad
• Arranged in telephone-line 3x4 + 4 extra keys, 16 keys in total
• Weight: 10 grams
• Keypad dimensions: 77mm x 77mm x 1mm (3" x 3" x 0.035")
• Length of cable + connector: 85mm
• 8-pin 0.1" pitch connector

• 1 x 4x4 Matrix Membrane Keypad

• How to Set Up a Keypad on An Arduino by Krishna Pattabiraman, Circuit Basics - Very detailed example of 3x4 and 4x4 keypad interface to Arduino UNO, include Arduino example code and explanation
• Using 4x4 keypad with Arduino, by Techmirtz, under Arduino project hub
• Keypad library by Mark Stanley, Alexander Brevig