Description: 16 way I/O extension module of the 12C interface, adopts MCP23017 chip of MicroChip. Each IO can be discretionarily configured as input or output, and can set pull up resistort. The IO configured as input can start interrupt function. The IO interface has a strong driving capacity, and the sink current and pull current can reach 25mA. MCP23017 is a high-speed IIC interface. It supports the IIC frequency of 100KHz, 400KHz and 1.7MHz. The chip has 3 address pins, which can set up to 8 different addresses. So 8 modules can be connected through two IIC buses to achieve up to 128 IO extensions. This module is flexible in configuration and strong in driving ability. There are many parallel connections. Specification: Operating voltage: 3.0V-5.5V Drive chip: MCP23017 Number of IO: 16 (input, output, interruption) Drive power supply: 25mAh 12C frequency: 100KHz, 400KHz, 1.7MHz Working temperature: -40? to 125? Chip level: Industrial grade Parallel multiple: Up to 8 Drive Program: 51 and Arduino Size: Approx. 65mm x 19mm VCC: Power source input, 3.0V-5.5V GND: Power negative electrode, 0V SCL: 12C clock line, SCL of connecting MCU IO pin or MCU 12C interface SDA: 12C data line, SDA of connecting MCU IO pin or MCU 12C interface RST: Chip restoration, Low level effective, connecting MCU IO pin or unconnected ITA: GPIOA port interrupt output, Connect MCU IO pin, without connection when interruption ITB: GPIOB port interrupt output, Connect MCU IO pin, without connection when interruption Package Includes: 1 Piece 16bit I2C Interface IO Extension Module 1 Piece 1*40 Pin Header 1 Piece 2*20 Pin Header