Welcome to our store! Compatibility Level: Changes in the state of an input port can generate an interrupt output (INT). Built-in level conversion circuit, compatible with 3.3V/5V working level. Support for 4 Expansion Modules: I2C communication address can be set, short circuit AO, A1 solder joint can modify the communication address, support the use of 4 expansion modules. I2C Interface Control: I2C interface control, only 2 signal lines are needed to expand 16 I/O ports. Current Control: The expansion module supports 16-channel common anode constant current LED drive, 256-step linear dimming and current control. Two Interface Types: The I2C interface expansion board provides two interface types, PH2.0 terminal and pad, and supports parallel connection of multiple I2C modules. Item Type: IO Expansion Board Material: PCB Working Voltage: 2.4-5.5V Working Temperature: Minus40 to 80℃ Control Interface: I2C Number of Expansion I/O Ports: 16 VCC: Positive power supply, can be connected to 3.3V/5V power supply GND: Power ground SDA: I2C data line SCL: I2C clock line INT: Interrupt output RST: Hardware reset Size: Approx. 38 x 23mm / 1.5 x 0.9in 1 x IO Expansion Board 1 x Dupont Cable Customers are our top priority. If you find any problems with your product after receiving it, such as damage or incorrect quantity, please contact us immediately. We strive to provide you with the best customer service.