USB-C Breakout and 3.3 V Regulator Building Block Board — Part 4#

Today I published the USB-C breakout and 3.3 V regulator building block board project.

The project is now available here:

https://github.com/johnktaylor/protoworks-kicad-3-3v-regulator

I have published it under the CERN-OHL-W-2.0 licence. The repository contains the KiCad project files, including the schematic, PCB layout, and bill of materials.

This is the first of my building block boards that I have published properly as an open hardware project. The goal is not to create a polished commercial product straight away, but to make the design available in a useful form so that others can inspect it, learn from it, modify it, or use it as the basis for their own projects.

Why Publish the KiCad Project?#

For this board, I decided to keep things simple.

Rather than exporting the design into lots of different intermediate formats, I have published the KiCad project itself. KiCad is open-source, widely available, and increasingly common in the hobbyist, open hardware, and small-scale engineering communities.

The repository includes the actual design files rather than just screenshots or PDFs. That means the schematic and PCB can be opened, inspected, modified, and regenerated properly.

I may still add exported files later if they prove useful, but for now the KiCad project is the primary source of truth. If I make any further significant updates to the design, I will update the project at that location.

What Is Included?#

At the moment, the repository contains the core KiCad project files for the board:

  • the schematic
  • the PCB layout
  • the bill of materials
  • the licence file

That should be enough for someone to open the project, inspect the design, understand the circuit, and generate their own production files if required.

I am deliberately keeping the repository lightweight. This is not intended to be a heavily managed software-style project with lots of process around it. The main value is the design itself.

Why CERN-OHL-W-2.0?#

I chose the CERN Open Hardware Licence, weakly reciprocal variant, because it fits what I am trying to do with these boards.

I want people to be able to study the design, modify it, and use it in their own work. At the same time, I want the project to remain clearly identified as open hardware, with the original design and licence terms preserved.

For this type of small hardware building block, that feels like a sensible balance. It is open enough to be useful, while still giving the design a proper legal and attribution framework.

Part of a Larger Idea#

This board is part of a wider set of building block boards I have been working on.

The idea is simple: create small, reusable, tested circuit modules that can be used in prototypes, one-off projects, and larger designs. Rather than repeatedly rebuilding the same support circuitry from scratch, I want to gradually build up a small library of known-good blocks.

This particular board combines a USB-C power input with a 3.3 V regulator, which is a fairly common requirement in small embedded projects. It is not exotic, but that is partly the point. A lot of useful engineering is about making ordinary pieces reliable, understandable, and easy to reuse.

Next Steps#

For now, this is the first published version of the project.

I may add more documentation over time, including additional test notes, usage examples, or exported manufacturing files if they seem useful. However, the main design files are now available, and the project has a proper open hardware licence attached to it.

That feels like a useful step forward.

The board started as a practical prototyping aid for my own work. Publishing it gives it a second purpose: it becomes part of a small, growing collection of reusable open hardware building blocks.

If you are looking for reusable open hardware modules to speed up your bench testing, or need support designing custom breakout circuits, check out our catalog at Protoworks (NI).