I'm following this project which shows how to make an OpenTherm Adapter for an Arduino. It includes this schematic:
Along with this simplistic PCB diagram:
I am now in the process of making my own version of this circuit on a prototype PCB board. This is my first time making anything more complex than a simple header wire circuit using an Arduino and has therefore posed a bit of a challenge. However, with the help of Fritzing, I have been able to prototype a board design:
I understand this is a messy design and has lots of room for optimisation, but my question is whether or not the design I have made matches the schematic in the first image above. I would really appreciate it if someone could look over my schematic and let me know.
Thank you in advance for you help.
P.S. Here is a link to where you can download the schematic file (
The circuit will be connected with a combination of excess solder and wires. Please bear this in mind where it may look like some tracks overlap. Feel free to download the file for clarification.