Multi-Channel Expansion: The module offers multiple configurable input/output channels, allowing you to expand a single I/O pin into many. Digital Input/Output: This expansion board supports both digital input and output, enabling you to input external signals into a microcontroller or output signals from the microcontroller to external devices. Low Power Consumption: Designed with low power consumption in mind, this multi-channel expansion board minimizes power usage during operation, making it ideal for applications requiring long-term use and extended battery life. Programmable Features: The expansion module is highly programmable, allowing you to set the working mode, polarity, and current drive capability of input/output channels through configuration registers. High Reliability and Stability: Built with premium components and reliable circuit design, this expansion module ensures high reliability and stability for your projects. Type: Module Condition: New Operating voltage: 1.65V to 5.5V J1-J2 single row pin spacing: 800mil (2.54mm x 8 = 20.32mm), suitable for access to breadboards All 16 IO ports have LED indicators The LED is designed with a common anode and uses a 2k resistor to limit the current; when the output of the IO port is logic 0, the LED lights up Specification: PCA9555A Color: Green Material: ABS Package Contents: 1 x Expansion Board Module Note: Light reflection and different displays may cause the color of the item in the picture to be slightly different from the real thing. The measurement allowed error is +/- 1-3cm.