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# MCP23017 IO Expansion Board, Expands 16 I/O Pins

**Type:** Product page · **SKU:** WS-15391 · **Brand:** [Waveshare](https://core-electronics.com.au/brands/waveshare-in-australia)
**Page:** https://core-electronics.com.au/mcp23017-io-expansion-board-expands-16-i-o-pins.html ([markdown](https://core-electronics.com.au/mcp23017-io-expansion-board-expands-16-i-o-pins.html.md))

The MCP23017 IO Expansion Board expands 2 signal pins as 16 I/O pins based on the I2C bus, up to 8 MCP23017 IO Expansion Board can be used at the same time, providing up to 128 I/O pins, it is compatible with both 3.3V and 5V levels.

## Pricing

- **Price:** $10.90 (inc GST) — $9.91 AUD, exc GST
- **Quantity discounts:** 10+ $9.51 (exc GST) · 25+ $9.22 (exc GST)

## Availability & dispatch

- In stock, ships same business day if ordered before 2PM (Australia/Sydney).
- We can dispatch 7 today, and up to 300 more in 12–19 days.

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## Description

The MCP23017 IO Expansion Board expands 2 signal pins to 16 I/O pins based on the I2C bus, up to 8 MCP23017 IO Expansion Boards can be used at the same time, providing up to 128 I/O pins, it is compatible with both 3.3V and 5V levels.

## Specifications

- Operating voltage: 5V/3.3V
- Interface: I2C
- Interrupt pins: INTA, INTB
- Expansion I/Os: 16
- Dimension: 38mm × 23mm
- Mounting hole size: 2.0mm
 
## Pinout

- VCC: 3.3V/5V
- GND: Ground
- SDA: I2C data line
- SCL: I2C clock line
- INTA: PA group interrupt output
- INTB: PB group interrupt output
 
## Dimensions

![MCP23017 IO Expansion Board dimensions](https://core-electronics.com.au/attachments/localcontent/MCP23017-IO-Expansion-Board-size_13670091024.jpg)

## Resources

- Wiki
 
## Shipping List

- 1 x MCP23017 IO Expansion Board
- 1 x JST-PH 6-Pin 20cm

## Images

- [Product image 1](https://core-electronics.com.au/media/catalog/product/m/c/mcp23017-io-expansion-board-3_1.jpg)