This is an IO expansion module based on the MCP23017 chip. It expands the microcontroller’s IO ports by adding an additional 16 digital IOs. With the ability to set 8 I2C addresses, the module can be used to connect up to 8 modules, allowing for a total expansion of 128 IOs. This makes it ideal for applications where there is an insufficient number of IO ports, such as in robots and interactive media.

The module has two groups of IO pins, labeled GPIOA and GPIOB, each with 8 independent IO interfaces. These interfaces can be programmed to function as inputs, outputs, pull-up inputs (with a 100KΩ pull-up resistor), or as interrupt pins.

Additionally, the module has two interrupt signals, IA and IB, which detect interruptions on the GPIOA and GPIOB interfaces respectively. When an interruption occurs on one of the pins, the corresponding IA or IB will produce a high-level signal.

Features:

Supporting to expand 128 IOs at most
Multiple IO mode
Changeable I2C address by dial switch
Multiple VCC and GND pins leaded
Compatible with both 3.3V and 5V

Applications:

Robots
Interactive medias
Light cube

Specifications:

Operating Voltage: 3.3V~5.5V
I2C Address: 0x20~0x27
Digital Input/Output: 20Ma
Signal Interrupt Pin: IA, IB
Dimension: 44x32mm / 1.73×1.26 inch