Lecture on Electronics Design

Emma gave us a very good lecture on basic electronics and how to design a board with Eagle.

Some notes

Kirchoff's circuit laws (Wikipedia)

  1. At any node (junction) in an electrical circuit, the sum of currents flowing into that node is equal to the sum of currents flowing out of that node.
  2. The directed sum of the electrical potential differences (voltage) around any closed network is zero.

Basic formulas needed to specify necessary board components:

Voltage V
V = R · I
Voltage V
Voltage or electric potential tension is the electric energy charge difference of electric potential energy transported between two points. (Wikipedia)
Resistor R
R = V ⁄ I
Ohm Ω
The electrical resistance of an electrical conductor is the opposition to the passage of an electric current through that conductor. (Wikipedia)
(Electric) current I
I = V ⁄ R
Ampere A
The flow of electric charge. (Wikipedia)
Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points. (Wikipedia)
Power P
P = R · I 2
Watt W

Basic symbols, among other, used to draw an electronic circuit:

Series and parallel circuits, please see Wikipedia

The Fab Academy’s Electronics Design - Eagle tutorial was my main guide to do the assignment.

Redrawing and Making an Extended Echo Hello-World Board

I watched some video tutorials showing how to work with Eagle. I thought of adding a sensor to the board. In order to use the board as an interface for a media installation, I would like to integrate a distance measuring sensor like the SHARP GP2Y0A710K0F. Finally, I decided to intergrate two 2-pin screw terminals in order to use different modules later. I started with the sample file of the echo hello-world board and added a slide switch in order to choose one of two connected modules. The 2nd 2-pin screw terminal is connected to the ground. Two LEDs show which module is selected.

List of addtional components:

Design files

Please download original Eagle design files here.

Milling the traces, I had problems again and I had to cancel the process. The board wasn’t fixed tightly enough and the bit didn’t properly mill the copper. Advised by Zaerc, I fixed it and got a perfect PCB.

Photos of production

I soldered all components on the PCB. Unfortunately, I didn't replace the JP1 connector of the sample file. I didn't know that it wouldn’t be available and I had to find a solution. So, I choosed a suitable 6-pin single row connector and bended its pins on one side. I extra solidly soldered this component. I was lucky. Finally, everything worked fine.