Feature: 1. Micro Bit IO Expansion Board: Powerful expandability with 19 pins, each with VCC and GND, allowing for multi channel function expansion and rich application scenarios. 2. Versatile Voltage Switching: Micro bit expansion board allows you to easily switch VCC of each pin between 3V3 and 5V, providing flexibility to adapt to various circuit requirements. 3. I2C Support: Specially led out I2C SDA and SCL pins and the corresponding 5V and GND pins, can be easily connected to LCD1602 LCD screen containing I2C interface modules, greatly simplifying the operation. 4. Independent Power Supply Design: 3 independent 3V3 and 5V pins for stable power supply, supports both DC power socket and USB power supply, suitable for various usage scenarios. 5. Integrated Noise Device: Equipped with a passive buzzer, users can connect and achieve various sound alert functions via via jumper cap, playing a crucial role in IoT devices. Specification: Item Type: IO Expansion Board Material: PCB Power Supply: USB 5V Power Supply, DC Power Supply (6-12V) With Power Indicator: Red LEDCharacteristic: Can carry 3.3V/5V load. Onboard a passive buzzer. Package List: 1 x Expansion Board 1 x User Manual