1. Why they’re green
When talking about PCBs, I believe that iconic dark green color will come to your mind. Have you ever wondered why this color? The green that you see is actually the color of the soldermask showing through the glass. When the origins of the use of the green is concerned, there are a few theories.
Some speculate that green was the regulation standard when PCBs were used by the American military, and the use of it spread from there. It has also been suggested that green could have been the color of the original solder mask resins, and that we continue to use green as a matter of convention, despite these materials are no longer used. Actually in modern circuits we see a soldermask made in any color, including yellow, black, and blue. Just name a few. However, green has worked well for us so far, and there is a cutting edge when using green, making it particularly easy for engineers to see faults in the traces. Maybe that’s why a lot of manufacturers tend to stick with it. I hope that can explain why the green comes to mind when people talk about PCB.
2. Who invented them?
Paul Eisler, an Austrian inventor, is generally known to get accredited for the invention of the PCB although the development leading up to the invention can be traced as early as 1890s. Eisler developed the first PCB when working on a radio set in 1936. However, PCBs saw mass usage till 1950s. And it got significant increase in popularity from there.
3. They are everywhere!
There is no doubt about the popularity of Printed Circuit Board. You pick up an electronic gadget at your hand and it makes use of one right now. There is a big chance that you are reading this from a device that contains a PCB. PCB has become a really integral aspect of modern tech, and as PCB technology itself is constantly evolving, we can not see any chance that any other creations will be replacing them in the near future.
4. They’re designed using CAD
You might not know that PCBs are designed using CAD, or computer aided design. Technicians use CAD programs to design both the schematic and the layout of the Printed Circuit Board. This allows the board design to be tested, checking that all the traces are properly connected before the PCBs are physically made. It decreases the possible errors in PCB manufacturing.
5. Surface mount technology
Surface mount technology (or SMT in acronym) is the most common manufacturing technique used to make modern PCBs. SMT became widely used in the 1980s and quickly replaced its predecessor, the through-hole method, which had been slow and incurred many errors. Whereas with through-hole the components had to be attached to the board by inserting component ‘leads’ into holes, SMT makes them glued onto pads on the PCB’s surface.
6. Traces other than wires
You probably know that electronic devices most commonly use wires as a means of transmitting energy. However, PCBs are exceptional to this convention. PCBs use copper traces instead of wires to transport electrons. Using copper traces in the place of wires allows PCBs more compactability, as the flat traces take up a lot less room. It also means that they can be made using through-hole technology, as the copper can easily transfer through a hole in the circuit board.
7. There are a lot of potential components
There are probably more components used in PCBs than you thought, and they all have their own individual properties. The list includes (but is not limited to) resistors, potentiometers, capacitors, inductors, relays, batteries, fuses, transformers, diodes and transistors.
Have you ever wondered about the white etchings that you seen on top of the green PCB soldermask? This is the silkscreen, and it is used on the component side of the circuit board to help identify components and other PCB information. The white text can be silk screen printed, which is the origin of the name. However it tends to be printed using digital by ink-jet printers nowadays.
9. They can be completely personalised
You can order them to suit the specifications you need from the PCB manufacturers. But there is no need to make every PCB to a unique specification since custom PCBs are costly in time and money.
10. The technology is always changing
PCBs have changed hugely since Paul Eisler invented it in 1936. Currently they’re much more smaller, faster, and efficient to build. However PCB technology is always evolving. Right now scientists are working on making PCBs that are biodegradable which means more environmentally friendly. Similarly, the development of the material ‘graphene’ could change the ways in which our electronics operate. PCBs are never static; the technology is always developing to get improved.