Provide two-way communication capabilities. Provide 3.3-5V, 1.8-3.3V, and other common level conversion capability. Serial communication interface compatible with UART/IIC/SPI port, easy to connect. Widely used in the MCU and SD card, MCU and serial devices, MCU and 5V/3V module communication. OE active high enable IO recommended by a low voltage side of the IO port. Dimensions: 3.46 x 2.64 x 0.55 inches.