Printed circuit boards, the resin-based boards that are filled with microchips, diodes, and electronic components that you see in computers and other electronic items, are made in bulk but companies all over the world. The process is a mix of automation and manual input, but if the board is not assembled correctly, the board will not function properly. Have you ever wondered how they are made?
Designing The PCB
Every PCB (printed circuit board) starts as a design on an electrical engineers computer. The board has to be designed to have the correct pathways for electricity to flow through without it getting diverted to a part of the board it does belong. The design process is very painstaking and can take a tremendous amount of time, even if you are using computer-aided tools to do the work. Once the board is complete, the prototype must be built and tested before the PCB goes into final production.
Building the Boards
Once a circuit board has passed the design and testing process, it is moved to the manufacturing floor. Most companies building these PCBs in bulk use a machine called a surface mount machine. The bare board is loaded into the machine where it is screen printed with solder paste then the machine places all the components on the board. In some cases, the board can be printed in one step, but there are some that are very complex, and the components need to be added in multiple steps. Once all the components are on the board, it passes to a high temperature over that melts the solder paste then cools it to solidify it and create the connections on the board. While it sounds simple, in truth it is a very complex operation that can go terribly wrong if one thing is off.
Inspection and Approval
Once the PCB is completed, an inspector looks at each board and verifies the position of the components, checks the solder and connections, and tests the board to ensure the connections are correct. In some cases they test every board, in other cases, they pull random samples to test. In the case of a custom circuit board, all this work would have to be done by hand. There are not many circuit boards being built by hand anymore because of the time it takes to do so.
Where Are These Printed Circuit Boards Used?
Printed circuit boards are everywhere these days. From your smartphone, tv, and DVD player to your dishwasher, washing machine, and even the car you drive. They are so efficient at distributing electricity to the right place, that they are a better solution than just about anything available before PCBs came to be. Look around, and you might just be surprised what has a printed circuit board in it.
For more information, contact your local PCB manufacturer.