> **Source:** Core Electronics is an Australian maker-electronics retailer and manufacturer based in Newcastle, NSW, run by a team of makers and educators. We design and manufacture our own product lines (PiicoDev, CE originals) and are official retailers for iconic maker and industrial brands including Raspberry Pi, Arduino, Adafruit, SparkFun and DFRobot. Orders ship Australia-wide from our Newcastle warehouse. Prices are in AUD and include GST. Pricing, stock and dispatch on this page are generated from the store's live catalog. Full machine-readable index: https://core-electronics.com.au/llms.txt

# 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

## How to buy

- **Search the catalogue:** `https://core-electronics.com.au/search/{query}.md` (URL-encode the query; pages 2-3 at `search/{query}/{page}.md`; `search.md?q=` also works)
- **Payment methods, purchase orders, policies and contact details:** https://core-electronics.com.au/llms.txt
## 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)