MCP23017 Datasheet, PDF: What is an I/O Expander?

Introduction of MCP23017 I/O Expander

The MCP23017 device is a 16-bit general-purpose parallel I/O expander to the I2C bus as well as SPI applications. This 16-bit I/O port is comprised of two ports with 8 bits. It is composed of multiple 8-bit configuration registers to control input, output, and the selection of polarity.

Features

16-bit input/output port expansion with interrupt output

Cascadable that can accommodate up to 8 gadgets per bus

25mA source and sink capability per I/O

Diagram

MCP23017 Pinout

CAD Model

Symbol

PCB Footprints

3D Models

Specifications

Supply Chain

Factory Lead Time – 12 Weeks

Physical

Package / Case – 28-DIP (0.300, 7.62mm)

Number of Pins – 28

Technical

Operating Temperature – -40°C~125°C

Where to Use MCP23017 I/O Expander?

The MCP23017 I/O expander is designed for general use and gives designers the capability to incorporate other inputs and outputs (I/O) on a microprocessor (MPU) or microcontroller (MCU) system.

How to Use MCP23017 I/O Expander?

The master system can set the I/Os as outputs or inputs through writing I/O-specific configuration bits. The information for each output or input is stored in the appropriate output or input register. The direction of the Input Port register is changed by a Polarity Inversion register. All registers are accessible by the master of the system. The MCP23017 I/O expander is able to be set to work in either 8-bit or 16-bit modes. The two interrupt ports are INTA and INTB, which can be connected to their respective ports to ensure that both pins will be activated in the event that either port triggers an interruption. In the Interrupt Capture, the register captures port values during the interrupt, and thus saves the situation which caused the interrupt. In addition, the Power-on Reset sets the registers to their default values and also initiates the device state machine. Hardware address pins serve in determining device address.

What is MCP23017?

The MCP23017 is an expander port that provides nearly identical PORTS when compared with traditional microcontrollers that come with interrupts. It provides you with an additional 16 I/O ports that use an I2C interface, as well as extensive interrupt control.

What is an I/O Expander?

A GPIO Expander is a device that gives a designer the possibility of implementing more input as well as outputs (I/O) on a microprocessor (MPU) or microcontroller (MCU) system. They feature a powerful data bus interface, which helps minimize the requirements for I/O of an MPU and MCU.

What is GPIO used for?

The GPIO is short for general-purpose input/output. The GPIO port is able to handle both inbound digital signals as well as outgoing ones. As an input port, it is able to send an ON/OFF signal to the CPU that comes from switches or digital readings that sensors receive.

Package Dimensions

About the Manufacturer

Microchip Technology Inc., is a leader that provides microcontroller and analog semiconductors. Microchip was headquartered in Chandler, Arizona. We are dedicated to offering low-risk product development, reducing total system cost, and accelerating time to market. We mainly serve different fields of customers applications around the world. To provide prominent technical support along with reliable delivery and quality is our goal.