Printed circuit boards have many advantages, making it the better option when building electronic devices. In the past, electronic devices are connected with large wires. These wires are placed anywhere they could fit it in. This method was very messy and definitely occupies a huge amount of space. PCBs on the other hand, use a different approach. This circuit is mounted on a non-conductive board and is connected with small pathways called traces. PCBs are designed either through a computer using computer-aided software or can be done manually using a felt tip marker and graphing paper. Most prefer the computer aided version of designing boards since adjusting the layout is easier. You can easily make layout to fit any component and occupy a minimum amount of space possible.
This so-called “miracle space saver” for electronic devices contains several parts. The most noticeable part of the PCB would be the traces. These thin lines are conductors (can carry electric charge from one place to another) and they serve to connect all the parts of the component in the circuit. Drilled on printed circuit boards are holes, the number of which is dependent to the chip which will be attached to it. The holes are created so that the electronic circuit is mounted completely without long leads and wires. The most important part of the PCB is the component itself. It can either be an integrated circuit (IC) or a microchip. The component performs the work of the circuit while the PCB provides the connection.
One can create their own printed circuit boards provided all materials needed are made available. Electronic circuit layout can be made through a computer using specific software. There is a lot of software readily available like PCB, Liquid PCB and Shortcut. A layout is important to ensure that a perfect arrangement of parts is created before making it permanent by soldering. The schematic layout of the circuit is literally printed on the board thus the name printed circuit boards. A raw circuit board has two layers: the non-conductive bottom made either of fiberglass or wood and the sheet of metal (most commonly copper) on top.
The layout created for the circuit is transferred to the copper plate in the circuit board using an etch-resistant substance. A good example of such substance would be asphalt, nail polish or the ordinary sharpie marker. A non-artist can use the ever-dependent laser printers to create the layout for the circuit board. The ink used in this type of printer is etch-resistant making it the best to use for your circuit board. Using a glossy paper print the layout created in the computer. Make sure that you selected the mirror printing option when printing. Place the glossy side of the paper with the print, on top of the copper plate. Iron the paper on the copper plate using ordinary clothes iron. The length of time depends on the type of paper and ink used. Once satisfied, immerse the board in hot water for a few minutes (maximum of 10 minutes). Remove the paper ensuring that the ink is left on the copper plate. You can now etch the board using a mordant, a mixture of acid and water. Remember to pour the acid on the water and not the other way around. The excess copper is removed and what is left is the design on the board. Holes are placed to attach the chip to the board.
Printed circuit boards are used in almost every electronic device in the market today. The biggest desktops to microwave ovens to small mobile phones use PCBs to organize wires inside the device. PCBs are indeed a revolutionary invention of man.
Printed circuit boards are a self-contained module of interconnected electronic components first introduced in the 1940s.