This version of my Millivolt Meter is an upgrade on my previous project version and uses a small PCB and Arduino Pro Mini.
The display now uses an I2C interface. The build now includes a Hold Reading and Bar Graph display. In addition the calibration method has been upgraded to use a 5 volt reference source. The latest version of software has also been improved resulting in a faster refresh rate. Below are links to download the latest software and also a zip file which contains PDF’s for the Schematic, Parts List, Wiring Diagram, Plate and Drill Templates and Front and Back Panel Artwork.