How much do you know about interesting PCB knowledge?

Without a doubt,printed circuit boards(PCBs)are a milestone tool in human technology.Why?This is because it is hidden in every electronic device today.Like other great inventions in history,PCBs have gradually matured with the progress of the wheel of history.It has a history of 130 years.This is the most beautiful scenery in the wheels of the Industrial Revolution.
PCB has become a means of optimizing the production process of electronic devices.In the past,handmade electronic devices had to be replaced by polychlorinated biphenyls.This is because more functions will be integrated into the circuit board.
Comparing the circuit boards in the 1968 calculator with modern computer motherboards
01 Color of PCB board
Even for some people who don't know what a PCB is,they usually know what it looks like.They at least look in a traditional style,which is their green color.This green color is actually the transparent color of solder mask glass paint.Although the name of solder mask is solder mask,its main function is to protect the covered circuit from moisture and dust.
As for why the solder mask is green,the main reason is that green is a military protection standard.The PCB in military equipment first uses solder masks on site to protect the reliability of the circuit.Green is the natural protective color of the military.Some people believe that the epoxy resin used in the original solder mask was green,so it is still in use today.
Nowadays,there are various colors for soldering masks,including black,red,yellow,and so on.After all,green is not an industry standard.
02 Who Invented PCB
If you ask who invented printing,then this honor belongs to Bi Sheng during the Northern Song Dynasty in China.But the earliest printed circuit boards can be traced back to Austrian engineer Charles Ducas in 1920,who proposed the concept of using ink to conduct electricity(printing copper wires on a substrate).He used electroplating technology to directly produce wires on the surface of insulators and made prototypes of PCBs.
The metal wires on the circuit board were originally brass,an alloy of copper and zinc.This disruptive invention eliminates the complex wiring process of electronic circuits and ensures the reliability of circuit performance.It was not until the end of World War II that this process entered the practical application stage.
03 White marking
There are still many white marks on the green circuit board.For many years,people have never understood why these white printed markings are called"screen printing layers".They are mainly used to identify information about components on the circuit board and other content related to the circuit board.
These pieces of information were originally printed on circuit boards through screen printing,hence referred to as the screen layer.Now,special inkjet printers are used for printing.These pieces of information can help circuit engineers check for any faults on the circuit board.
04 Components
The function of a circuit board is mainly achieved by effectively connecting components according to the schematic diagram.Each component has its unique functionality.Even two closely adjacent devices on a circuit board can be very different.The types of devices basically include resistors,diodes,transistors,capacitors,relays,batteries,transformers,and many other devices(such as fuses,inductors,potentiometers,etc.).
05 PCB is ubiquitous
It is not an exaggeration to say that polychlorinated biphenyls are ubiquitous.From computers to digital clocks,from microwaves to televisions and stereo systems.As long as it is an electronic item and device,there is a 99%chance of including polychlorinated biphenyls.So we can assume that without a PCB,any electronic device may not be able to operate.
06 NASA
Some groundbreaking technologies have been used in many projects of the National Aeronautics and Space Administration(NASA)in the United States.In the 1960s,NASA used PCBs on the Apollo 11 rocket.This is because electronic products based on PCBs.This device is lightweight and consumes less electricity.That was the greatest moment of humanity,the first time an astronaut was sent to the moon.Among them is the contribution of PCB.
07 Surface Mount Welding Technology
Surface mount welding technology modernizes printed circuit boards.Compared to previous socket installation methods,this surface mount soldering technique first uses special glue to attach the device to the PCB,and then connects the device to the circuit board through special reflow soldering.
08 Rapid Prototype PCB
In the local experimental process of the circuit,universal circuit boards such as bread boards and orifice boards can be used for testing.With the increase of surface packaged components,new rapid PCB forming technologies have emerged,such as heat transfer printed PCBs,3D printed multilayer circuit boards,etc.
09 Flexible PCB
PCBs are not always straight and hard,and there are many flexible PCBs that can work in many compact electronic devices.They often form application circuits in many movable joints or form multi-layer three-dimensional circuits.