8. Electronics production

Group Assignement

This week I learned different options for bringing electronic design to life. Now I know that this came be done through several methods... some more sustainable than others. This processes can use mills, chemicals or blades to give shape to our PCB before all components are soldered on them. Another process that requires some practice.

Some of of my learnings:

Unfortunately it is not that fast and easy to find SMD components in my city.
Copper tape and a mini plotter can do magic with a bit of creativity, care and several tests.
There are many options for PCB production, but the information about it is all scatered.
The only PCB mill available at my campus is not very easy to access.
It is VERY important to find the right footprints and schematics before production.
If the right footprints and schematics are not available, it is always possible to create them.
Both woftware and hardware have to communicate and be compatibl, so always double-check details.

Routing on campus

My first attempt to tackle this assignement was about milling a copper board at my campus' labs. I went around asking for the place and person that could help me only to find out it has a waiting list protocol and students are not normally involved in the process. I'm still waiting on the permission and scheduling of my turn. (One week later)

This is the lab and forms I am talking about.

Tape test (mini project)

As a second attempt I tried getting copper tape and using a plotter. Before soldering anything or adding a microcontroler, I decided to test a very simple circuit to see if the tape worked. I had so much fun with this mini project:

First things first: testing the conductivity and connections for the mini project. (Coin battery, copper tape, resistor and LED)

Then I made an sketch that would give this circuit a personality

I printed the sketch with a marker in the plotter (first time ever doind this)

The next step was to prepare the copper and the design for it

The first cut wasn't so good because I didn't choose the material right. At least this cut worked to test size and shapes.

I realized I had to make everything bigger and further appart, so I made the necessary adjustments:

For the following copper cut I did choose the right material

It felt like a background was missing, so I quickly painted one by hand and started pasting everything in place

I am so happy with the final outcome:

Besides the mini project, I checked that soldering over the tape wouldn't be a problem and fortunately it works well:

Final PCB Design

Now the next step is finding the right footprint and schematic for the microcontroler I was able to get: ESP32-C3-Zero.

Here is some useful information about it:

I wasn't able to find the schematic or footprints for this exact microcontroler :( So I asked ChatGPT if it could help me create them:

Although it seemed like files were created and I was able to upload them to KiCad, when I tried using them nothing showed up:

So I started creating my own files. Starting by editing an existing footprint to match my size, position and needs:

Then I also created my own schematic from a similar one, making sure all pins where named and configured correctly:

Then I got a simple Code ready with Arduino IDE, not knowing I would be having trouble uploading it to the board.

The first mistake was using the wrong cable (only charging, no data) and not choosing the right COM.

After that, I went back to read the documentation and noticed an additional board manager had to be manually installed, so I did that:

With that, I was finally able to upload the code.

Then I came back to the physical world to try out all components and connections:

After that, I finally got to design the full schematic of the circuit. Adding my LEDs, resistors, a button and connecting evrything together:

The next step was to design the PCB footprint from the schematic. But when I imported the components, I noticed the resistors qhere missing, so I tried adding them manually:

But then, when I tried connecting the components, I wasn't able to connect some together:

I looked for the reason and it turns out that the resistors I was using did not have a footprint assigned and you can't just add components manually because the have to be referenced in the schematic, creating a single net. So I assigned the footprints that matched my components in the schematic and then the connections appeared as they chould: