DFRobot has released the RainbowLink-V2, a compact USB-to-serial converter that bundles four independent channels into a single device. The tool provides one isolated RS-485 interface, one isolated RS-232 interface, and two TTL interfaces, all usable simultaneously through a USB Type-C connection. The device measures 7.7 cm (3.0 inches) by 5.7 cm (2.2 inches) by 2.1 cm (0.8 inches) in its plastic housing and supports baud rates from 2400 to 128000 bps across all channels.
Beyond serial conversion, the RainbowLink-V2 functions as a multi-voltage power supply, converting the 5V input from USB-C to 12V at 800mA, 5V at 2A, and 3.3V at 200mA outputs. This eliminates the need for separate power adapters when working with sensors or development boards. The device includes built-in overcurrent and short-circuit protection, along with seven LEDs indicating power status and link activity for each serial channel. RS-485 and RS-232 connections use lever-type spring terminals supporting 12AWG to 22AWG wire, while the TTL interfaces use standard headers.
The converter works with Windows, Linux (including Raspberry Pi), and macOS as a standard USB serial device. The CH343 chipset inside the RainbowLink-V2 is fully compliant with the CDC (Communications Device Class) standard, which means Linux kernels 4.x and newer recognize it automatically through the built-in CDC-ACM driver without requiring manual driver installation. DFRobot provides CH343 drivers for Windows users and basic documentation on the product wiki. The multi-interface design supports debugging tasks alongside connecting GPS modules, RS-485 soil sensors, or RS-232 industrial PLCs simultaneously.
The RainbowLink-V2 sells for $25 (€23). DFRobot also offers an earlier RainbowLink model at a lower price, but the V2 adds 12V power output and isolation on the RS-232 and RS-485 channels.
