Electronics design

Assignment - Electronics design

  • I -- group assignment:
  • - use the test equipment in your lab to observe the operation of a microcontroller circuit board
  • II -- individual assignment:
  • redraw an echo hello-world board, add (at least) a button and LED (with current-limiting resistor)check the design rules, make it and test it extra credit: simulate its operation

Individual assignment:

To solve the task assignment I followed the instructions on the page: Kicad Electronics design

I installed the program from the site: Kicad

Then I made new project - Atiny45.pro

Next step was to create schematics with Eeschema

Then I had to import libreries - fab.lib - with FabLab electronic parts symbols

After that, I started drawing the scheme by placing and connecting - wiring the symbols

After I inserted the symbols it was necessary to connect them. I made the connection using the wire command.

After drawing the symbols and adjusting their settings I generate a netlist and after that I was ready to make PCB

After trying to place the symbols my PCB had the following look

It was time to make .png from .svg that I made in KiCad.

For making png I used Inkscape

Each layer of the scheme - traces, outline and background is placed on its own layer, so that new layers are made and transfer each part to the appropriate layer.

I made export of outline.png and traces.png adjusting properties

The end result is

I made import of outline.png and traces.png into fabmodules

and make calculate

However, while we were doing this task - since we are not in FabLab itself, but working remotely, I was not able to work on a CNC machine. For that reason, I made this tile in a slightly different way. I took a photo sensitive tile and cut a piece.

To make a PCB this time I used an etching method. After the PCB is exposed to the UV light it goes into the developer and then in a etching solution. Whole process can be seen in Electronic production week. The results can be seen in the following image.

For etching I used hydrochloric acid with hydrogen peroxide in a ratio of 2: 1. With gentle stirring after 3 minutes the pcb was removed from the acid and washed with water.

After washing and sanding it was time to solder.

And the result is ...

Testing the PCB

I followed the instructions on the page: Programming ATtiny85 with Arduino Uno I programmed a simple sketch. When the button is pressed, the LED lights up.

Sketch code in arduino

Video blink:

Group assignment:

For the group assignment we had to use the test equipment in our lab to observe the operation of a microcontroller circuit board. I used digital multimeter to read voltages.

I measured the voltage when the led is on and off. You can see in a picture measured voltages.