DIY Printed Circuit Board Guide
Fri, Dec 13, 2019
Have you ever thought of making your own robot, computer, or another form of electronic devices, the first thing you need is to create a Printed Circuit Board?
Paul Eisle invented PCB in 1936. Today, technology has become the linchpin for almost all the wired devices we use, e.g., cars, computers, cell phones, and so on. In any electronic device whose work involves computation, there are high chances that PCB is used. The technology coordinates all the electronic signals to meet the intended purpose of that device. Technology plays the role of the brain in most of the electronic devices we use today.
PCBs contain a unique glass-reinforced epoxy laminate material. They are green in color, but may also contain other colors too. The board is physically smooth and decorated, but it has some other built-in parts.
Design Schematics when making the PCB
This is the initial step; before creating a CPB, you must first have a clear idea of how you want to use it. The schematic will be your framework on the PCB layout. You may either borrow a readily designed schematics diagram or create one from scratch. The first thing is to draw the circuit on paper, then create it on a design tool, e.g., Cadsoft eagle.
Now that you have the schematics drawn in your design tool, you need to draw the circuit board. You need to create a structure of the wires that connect different parts. The process is something like a game of “connecting-the-dots,” you may have enjoyed sometimes in your life.
When creating the diagram circuit, you have already set the different parts that need to connect. You now need to join all the dots to connect different parts that need to work together, and the program will then show if everything is working correctly.
Getting the board done
After drawing the structure, it is now time to create the board. You may create it from your diagram or look for a professional manufacturer to create it for you.
Manufacturing Printed Circuit Board
If you are wondering how you can make a custom PCB, the first step is to have CAD software installed on your computer. You then need to come up with the PCB prototype.
Then you need to print the circuit diagram on the board using a photosensitive coating. After this step, you need to etch out the undesired copper from the board to form copper traces. This process is known as photoengraving.
There are two other methods for making traces. Silkscreen printing uses etch-resistant paint to cover the areas where the copper traces will be applied. The other way is PCB milling, which uses CNC machines to remove the unwanted copper.
After applying the copper track on the board, drill the holes to create a path for assembling the electronic parts. Special Tungsten Carbide drill bits are the most appropriate for drilling the holes. You must then coat the holes to create a connection between different layers.
Here you need to cover the board entirely, leaving the holes and pads. You can use materials like lead solder or copper. The last step is screen-printing, which involves printing the text on the PCB.
Testing Of PCB
Before joining the parts or delivering the circuit boards, you need to do a thorough test to look for shorts or opens that may result in malfunction. A short indicates that there are some undesired connections, while an open indicates a disconnection between two parts that ought to have been connected. Ensure that such errors are rectified before the PCB assembly. Please note that not all shops test their boards before shipping them. Although it may increase the costs, testing is important, because it confirms that the board is fully functional before adding other components.
Once the board is complete, you can assemble the parts to match the circuit diagram. The mostly used assembly methods include through-hole construction and surface-mount construction. You may apply a combination of the two methods for assembly
Types of Printed Circuit Boards
This is one of the simple PCBs, which contain only a single substrate. All the components are attached on one side while the copper traces are fixed on the other side.
This is the most common type of PCB, which has parts attached on both sides of the substrate. The two-sided PCBs use a through-hole model for the assembly of parts
This has different layers of substrate divided by insulation. The multilayered boards are rarely used unless for very complex electronic circuits.
PCBs may contain between two layers to forty-two layers, for electronics with more sophisticated technology. It is important to do a thorough analysis and understand the role that the PCB is intended to perform in a device before determining the number of layers to use.