M-Bus UART converter

Simple M-Bus to 3.3V UART level converter for 1..3 M-Bus slave devices. Board is designed to fit into off-the-shelve Kradex Z105 DIN enclosure. There are two options to power the board – either using an external 34V DC power supply connected to directly to the 34V input or with the optional DC-DC boost converter and 5V power supply.


  • M-Bus voltage: 34V
  • M-Bus slaves: 1..3
  • UART level: 3.3V
  • UART connector: 3.5mm screw terminal
  • Supply voltage: 34VDC
  • Optional on-board CN6009 5V-34V DC-DC converter
  • Short circuit protection: none
  • Single layer PCB
  • Dimensions: 86x14mm
  • Board fits into Kradex Z105 DIN enclosure



  • First home-made SMD prototype is working
  • Waiting for PCB-s from the board-house