USBtoUART

A USBtoUART device is a bridge that converts data between USB and a UART serial interface. It allows a computer to communicate with devices that use asynchronous serial signals, such as microcontrollers, sensors, or other embedded peripherals, by presenting a USB connection as a virtual serial port to the host.

Most USBtoUART adapters contain three components: a USB-to-serial bridge controller (for example, FTDI FT232R, Silicon Labs CP210x, CH340, or Prolific PL2303), level-shifting circuitry, and sometimes a voltage regulator. On the host side, the device appears as a USB peripheral; on the device side, it provides UART signals at TTL levels (commonly 3.3V or 5V) or, less commonly,RS-232/RS-485 levels.

The USB interface handles data transfer, while the UART side carries asynchronous serial signals with configurable baud rate, data bits, parity, and stop bits. Many adapters support both 3.3V and 5V operation and can supply limited power to a target device from the USB bus. The adapters typically require drivers to create a serial port on the host, with Windows exposing a COM port, and Linux/macOS exposing devices such as /dev/ttyUSB* or /dev/cu.* entries.

Common use cases include programming and debugging microcontrollers (as in Arduino or embedded projects), establishing serial console access, and connecting to serial sensors or modems. While most modern operating systems include generic support for popular bridge chips, some devices may need vendor-specific drivers or firmware updates.