Electronics Design

This week, our assignment was to design an echo hello-world board from scratch. We also had to include a button & LED into our boards. Our fab lab chose to learn with Eagle's printed circuit board design software. We had to download the fab library, and open it in Eagle to lay out the correct components. My design had so many errors the first time, I started all over again, taking care to lay out everything just right. It was tricky laying out connections correctly, I tried to follow the board diagram, but even then, some of my traces were backwards! I also added a button and LED.

I finished designing the board in Eagle a second time. Double check that your traces are named or snapped correctly, you can do this by naming both traces or picking up the component and see if the traces go along with it. If traces aren't snapping in the correct spot, you can hold down the alt key to get a more accurate placement. Make sure when routing board, to make all clearances 12 mil. Once you're working on the board file, it may be necessary to manually shift your traces for extra clearance or placement. I was able to resize and export the schematic file using Adobe Photoshop & Inkscape. Milling the board was a great learning experience, because I made many mistakes! The one up front was my first, this is what happens when you don't have your files dots per inch set to 600. Another board had the wrong bit, be sure to use a 1/64 not the 1/32! Once the board became loose because I was skimpy on the double sided tape! I finally succeeded in milling the traces, and made a vinyl sticker stencil to lay out the solder paste where the components would go. I also tried soldering by hand and as you can see it looks a bit messy. After a quick bake in the oven at 500 degrees, I had to solder the ftdi-smd header as they wouldn't have baked on otherwise. Much to my dismay, I accidentally dropped a giant blob of solder on the AtTiny circuit board. Not knowing much about electronic components, I thought my board was toast. Then a kind friend showed me the magical ways of flux and copper braid and my board was saved!