# 3x4 Matrix Keypad

**Type:** Product page · **SKU:** ADA3845 · **Brand:** [Adafruit](https://core-electronics.com.au/brands/adafruit-australia)
**Page:** https://core-electronics.com.au/3x4-matrix-keypad.html ([markdown](https://core-electronics.com.au/3x4-matrix-keypad.html.md))

## Retired product

This product is retired and no longer available for purchase. Replaced by: CE09447.

**Replacement:** https://core-electronics.com.au/catalog/product/view/sku/CE09447

## Description

Punch in your secret key into this numeric matrix keypad. This keypad has 12 buttons, arranged in a telephone-line 3x4 grid. The keys are connected into a matrix, so you only need 7 microcontroller pins (3-columns and 4-rows) to scan through the pad. Check the tutorials tab for links to an Arduino library and example code.

Adafruit include some header so you can plug this into a breadboard with ease, some light soldering is required to attach it. Or you can use plain wires if you like.

There's a great Matrix Keypad Arduino library that should work great with this item with minor adjustments. It's basically a sturdier version of Adafruit's [Membrane 3x4 Matrix Keypad](https://core-electronics.com.au/membrane-3x4-matrix-keypad-3x4.html). Note that the rows and columns are intermixed. The order from left to right is COL2, ROW1, COL1, ROW4, COL3, ROW2, ROW1

[We also have a 4x4 version of this matrix keypad](https://core-electronics.com.au/4x4-matrix-keypad.html) and [a version that has phone-styling with letters printed over the numbers](https://core-electronics.com.au/3x4-phone-style-matrix-keypad.html)

If you dig Adafruit's demo, check out the [Adafruit FeatherWing OLED - 128x32 OLED](https://core-electronics.com.au/featherwing-oled-128x32-oled-add-on-for-all-feather-boards.html)

There is a very nice Matrix Keypad Arduino library that works great with this item. The only thing we suggest is to change the initialization code in the examples to this:

 ```
#include "Arduino.h" #include "Keypad.h" const byte ROWS = 4; //four rows const byte COLS = 3; //three columns char keys[ROWS][COLS] = { {'1','2','3'}, {'4','5','6'}, {'7','8','9'}, {'*','0','#'} }; byte rowPins[ROWS] = {12, 5, 6, 10}; //connect to the row pinouts of the keypad byte colPins[COLS] = {11, 13, 9}; //connect to the column pinouts of the keypad Keypad keypad = Keypad( makeKeymap(keys), rowPins, colPins, ROWS, COLS ); void setup(){ Serial.begin(9600); } void loop(){ char key = keypad.getKey(); if (key != NO_KEY){ Serial.println(key); } } 
```

This will swap the \* and # keys and also let you connect to the Arduino with all the pins in order/in a row starting from digital 2 thru digital 9

## Technical Details

- Force: 160-180g
- Contact Resistance: <100 Ohms
- Product Dimensions: 70.0mm x 51.0mm x 9.7mm / 2.8" x 2.0" x 0.4"
- Product Weight: 17.6g / 0.6oz
 
## Resources

[Adafruit's detailed guide with wiring diagrams, libraries and example sketches for all sorts of matrix keypads.](https://learn.adafruit.com/matrix-keypad)

[Diagram](https://core-electronics.com.au/attachments/uploads/3845_Diagram.jpg)

## Images

- [Product image 1](https://core-electronics.com.au/media/catalog/product/3/x/3x4-matrix-keypad-3845-1_1.jpg)