I2C Level Converter Documentation


The I2C Level Converter allows you the run 3.3v logic sensors like the Bar30 or Celsius and other accessories off of a 5v logic device like the Arduino Uno. Attempting to run the Bar30 or Celsius off of a 5v logic device without a level converter will result in improper operation, and ultimately damage the sensor. A selectable solder jumper lets you power your instrument at 3.3v or 5v, independent of the 3.3v logic level.


Function Diagram

Specification Table

Operating Voltage 3.3-5v
Maximum Current 3.3v Vout 150mA
Output Connector 4 pin 0.1” header
Input Connector 4 pin 0.1” header, JST-GH, DF13
Length 34 mm 1.33 in
Width 11.6 mm 0.46 in
Height (without header pins) 6.5 mm 0.25 in


The EagleCAD files for the schematic and board are available on our GitHub page.

2D Drawings

3D Model

All 3D models are provided in zip archives containing the follow file types:

  • SolidWorks Part (.sldprt)
  • IGES (.igs)
  • STEP (.step)
  • STL (.stl)
I2C Level Converter  


To use the I2C Level Converter, first determine if your 3.3v logic instrument should be powered by 3.3v or 5v. Although they are 3.3v and 5v power tolerant, we recommend that the Bar30 and Celsius are powered by 5v for best performance. The solder jumper is set to 5v by default, but it can be switched if necessary. Plug your instrument into one of the input ports (4 pin 0.1” header, JST-GH, DF13) and your 5v device to the host device output port, and your instrument is ready to be used.