Category Archives: Electronics

The Stages of PCB Fabrication

Whenever an electronic device stops working properly, there is often a huge chance that a component on the printed circuit board (PCB) has come loose or is damaged. This means that the device owner would either have to get the device’s PCB fixed or just throw it in the trash and buy a new one. Most of the time, if the damage is on the PCB, it would be more cost-effective to buy a completely new device. But what exactly is a printed circuit board or PCB?

In layman’s terms, the PCB is the heart that keeps a device running smoothly. It is responsible for receiving signal and power from external sources. It is also responsible for distributing this throughout all the components of the device. It is referred to as a printed circuit board because of the way that a circuit made up of different components is mounted on a flat board that has a schematic diagram for interconnections printed on it. This diagram is often created even before the first stage of the PCB fabrication process begins.

printed-circuit-boardThe first stage of PCB fabrication involves etching the schematic diagram on the circuit board. Note that the board is often made up of sturdy fiberglass with a thin layer of copper sheet attached to it. The schematic diagram is important because it indicates the places on the board where holes have to be pre-drilled. These holes would serve a purpose later on when it when it is time to mount the components.

There are two different ways of mounting the components in PCB fabrication:

1.Surface Mount – this method involves mounting the components onto the surface on one side of the circuit board using a soldering iron. Because only one side of board is used for mounting and sticking the components, this leaves the other side free for the manufacturer to do with as he pleases.

2.Through-hole – this is where the pre-drilled holes come in handy. Although some manufacturers prefer to leave the holes untouched, others use it to secure the components. This is done by pushing the tip of the component onto a hole and then gluing that tip on the other side.

This requires thin copper or lead wires to be attached to the tips of each component so that the wires can be pushed through the holes and glued on the other side. Through-hole technology is the traditional way of mounting PCB components and has been in use from the time that PCB fabrication began.

After mounting the components, the circuit board would then be cleaned free of any solder paste residue. Manufacturers often use solvent for this purpose, though is also a good alternative.

It has to be noted that PCB fabrication involves a lot of cross-checking in order to ensure that everything is in order. This cross-checking includes both visual checks to verify if there is any visible flaw and electronic checks to ensure that every component is receiving the right amount of power. Some manufacturers put their finished products to the test u der extreme conditions, such as under strong heat or with high levels of vibration.

This would help ensure that the components wouldn’t come loose or get damaged at the first sign of trouble. This step is necessary when creating the PCBs of devices used in extreme sports or under extreme environmental conditions.

Techno geeks who want to experiment on PCBs can actually assemble their own PCBs right in the comfort of their homes. All they have to do is to purchase a handy PCB DIY kit and follow the instructions on the label. They wouldn’t even have to worry about having to create and etch the diagram since most kits already have printed diagrams on the circuit board.