USB to TTL UART RS232 with Voltage Translator



The Smallest USB to UART working at max 3 Mbaud and 3.6V to 0.8V

  • Today the most low voltage MCU and FPGA are working below the 3.3V, the usual USB-UART converters are not compatible with such voltage level.
  • So we decided to design our own customized board, with only the essential pins and the possibility to work at 0.8V.

What makes it special?

Thanks to the voltage translator 74AVCH1T45, you can use a UART port down to 0.8V

  • The voltage levels of TX and RX are the same of your target board power supply. This means that it doesn’t matter if your board is working at 3.3V or 1.5V or 0.8V, the logic levels are always correct!

Technical data

  • FTDI FT230X:  baud rates from 300 baud up to 3 Mbaud
  • Compatible with Windows, Linux and MAC
  • Size of 36 x 13mm
  • Working at 0.8V up to 3.6V
  • TX and RX LEDs indicators
  • Micro USB connector
  • Standard 2.54mm 4 pins female header
  • Protected by a transparent heat shrink sleeve


Name Description Direction Voltage level
+ Positive power supply Input 0.8V – 3.6V
Ground Input 0V
RX UART RX Input same of +
TX UART TX Output same of +