Keywords: Printed Circuit Board, Printed Circuits, Circuits Board

If you have ever peeped into electronic equipment, you might have noticed it contains a printed circuit board otherwise called PCB. They are green, flat, and thin rectangular substrates often covered with a maze of silver pads and fine copper lines. These circuits are considered the soul and heart of a majority of electronic equipment.  Before getting into the components used on this circuit, processes and methods involved in the manufacturing, you must first get into the basics of PCBs, their types and applications in various fields. This article contains what the PCBs are, their history, types and applications.

History of the printed circuit board

During the 1950s, point-to-point construction was replaced by the printed circuit boards in most electronics. Boards stamped with metal loops and wires soldered to terminal strips were used in Point-to-point construction. The wires of the small electronic components and wires from the larger devices like the transformers were soldered directly to the terminals, in a point-to-point operated device. Thus, you can easily imagine the system involving tangled wires. As every part and wire had to be soldered and looped following the right part of the terminal strip, this system was inconvenient to be used. 

Wire wrap was another way involved in the manufacturing of circuit boards in the 1960s. Wire interconnected every electronic component, which was mounted on an insulating board. The wire is used to wrap various times around socket pins or leads. Then, the boards with Printed Circuits evolved, which replaced almost every wiring made use of in the wire wrapping and point-to-point construction. This facilitated mass production.

Manufacturing of printed circuit board

The manufacturing process of PCB can be hugely automated. It decreases the engineering flaws risk that could lead to faulty boards of failed prototypes. The specifications of the circuit are input into the software. Extensive checks of design are run by this software for ensuring the optimal performance of the board before fabricating it. Low cost as compared to other methods of construction is facilitated by automated production. 

Printed circuit board Types

Various kinds of PCBs are used presently. Their construction method characterizes Printed circuit boards, which includes multilayer, double-sided, and single-sided board configurations.

Single-Sided PCBs

Only one substrate layer is present in Single-sided PCBs. A thin layer of metal covers the substrate on one side. As copper has high electrical conductivity, it is used generally. For signals and power between various electronic components, a conductive path is created by this layer. Next is the protective layer of the solder mask and the addition of silkscreen coating as a final layer for labelling the board parts. For simple electronics, Single-sided PCBs are used. As compared to other PCB types, these are found at a low cost and are mass-produced.

Multilayer PCBs

Multiple substrate layers are present in Multilayer PCBs. The layers are separated by insulating materials. The same technology as the double-sided PCBs is used in them. Surface mounting or through-hole methods are used for connecting the components on the multi-layer boards. Usually, four to 10 layers are present in the Multilayer boards. They can also have more layers as demanded by the product.  They are used for specialized applications like the medical specifications PCBs, servers, and computers usually.

Double-Sided PCBs

As compared to single-sided boards, Double-sided PCBs are used more commonly. The reason is two sides of the double-sided PCBs enable more complex circuitry. These also contain one substrate, but circuit components and conductive metal cover both sides. For connecting the components, either surface or through-hole mounting is used.

Small wires or leads are used in the through-hole mounting method. To their respective circuit or component, the leads are soldered at every end. Either this is done through automated insertion with the help of mount machines or done manually. For circuits needing to tolerate more stress, the through-hole method is used. This is because the combination of soldering and the leads through the Circuits Board facilitates a secure connection. These PCBs are used for aerospace and military products usually.

Holes are not required to be drilled in the board by Surface mounting. You can directly mount the Components onto the PCB. This method uses no leads or smaller leads are included in this method. As compared to the through-hole method, the surface mount PCBs are more popular due to low processing and handling costs. The components are soldered to the board either by hand or in bulk. 

Applications of the printed circuit board

Various types of PCBs are used in a variety of other fields apart from their use in computers and consumer electronics. They are:

Industrial machinery: High-powered industrial machinery makes use of PCBs commonly. PCB with thick copper is used in areas where PCBs with current one-ounce copper are not applicable. Industrial load testers, battery chargers of high-current and motor controllers are situations that benefited from PCBs with thicker.

Medical devices: Unlike the previous generations, Electronics products consume less power and are denser now. This enables testing exciting and new medical technology. A high-density PCB is used by most medical devices. This PCB creates the densest and smallest possible design. Some of the unique constraints involved with developing devices are alleviated by this for the medical field because of the demand for lightweight and small size. Starting from small devices like pacemakers to huge devices like CAT scan machines or X-ray equipment, PCBs have a huge range of medical applications.

Aerospace and automotive industries: Flexible PCB is used in both the aerospace and automotive industries. The PCBs are meant to handle environments with high vibration. They can be lightweight based on design and specifications. This is essential during the production of parts to be used in the transportation industries. These also can fit in the tight spaces present in such applications as the behind dashboard instrument gauge or within the instrument panel.

 Lighting: LED-based lighting is quite popular due to its low consumption of power and high-efficiency level. In the same way, the PCBs with aluminium used in such LEDs are popular too. Unlike the standard PCBs, more extent of heat transfer is facilitated by these PCBs, which act as heat sinks.  These PCBs with aluminium are used both in basic lighting and high-lumen LED solutions.

Conclusion

The demand and popularity of digital electronic devices keep on boosting like the internet, artificial intelligence, and robotics transforming our lives. This indicates that demand for the printed circuit board is also increasing and has a bright future.