4x4 Matrix 16 Keypad Keyboard

A 4x4 matrix keypad is a small input device with 16 buttons arranged in a 4-row by 4-column grid. It’s commonly used in embedded systems, Arduino projects, and access control systems like PIN pads.

 Key Features:

• *16 keys (0–9, A–D, , #)
• Matrix layout: 8-pin interface (4 rows + 4 columns)
• Compact and easy to integrate
• Typically uses membrane switches for reliability

How It Works:

• Each button connects one row to one column.
• The microcontroller scans rows and columns to detect which button is pressed.

Typical Uses:

• Keypad door locks
• Calculators
• Menu navigation for LCD displays
• Password or PIN entry systems