Posts in Category: Electronics

The Basics of Printed Circuit Boards

Today’s society, especially the industrial sector, relies on technology. Business processing, communication and education are just some of the uses of these technologies. Computers, smartphones and other electronics have become an essential aspect of a person’s daily living. Therefore, it is important to know more about these electronics and how they work.

Printed circuit boards or PCBs, are self contained modules of electronic components that are interconnected to each other. The circuits in a PCB are created by incorporating a thin layer of conducting material that is printed on the surface of a “substrate”, an insulating board that serves as the backbone of the printed circuit board.

Design

There is no set of standards that define how printed circuit boards need to look like. Each board has its own unique function intended for a particular electronic device. Therefore, each PCB needs to incorporate its own unique design in order to ensure that the electronic device functions properly. Although, there are no standards for design, manufacturers still need to follow certain protocols to ensure the quality of production of PCBs.

Printed Circuit Boards

Basically, the gaps between electrical conducting paths need to be around 1 millimeter or .04 inches. There are also instances wherein the measurement will be much smaller than that. The locations of the holes for the component leads are carefully laid out. This information will be translated into instructions for a computer-controlled drilling machine for the production process.

Materials Needed

Most printed circuit boards in the market come with a substrate made from fiberglass epoxy resin with a copper foil bonded to either one or both sides of the printed circuit board. There are also cheaper alternatives in the market. These inexpensive PCBs are made from phenolic resin, particularly the paper-reinforced variant. This type of PCB is usually used in household electronics.

The printed circuits are essentially sheets of copper, which are etched away or plated on the substrate. In order to prevent oxidation, the copper circuits are coated with a tin-lead layer. The contact fingers are usually covered with a tin-lead material. After that, nickel and gold can be added for better conductivity. Some other components in a PCB include the transistors, capacitors, resistors, diodes and other electronic components.

Quality Control

In order to ensure that PCBs are in utmost quality, it is important that visual and electrical inspections need to be conducted all throughout the production process. This is to help detect any flaws or defects among the PCBs that are being mass produced. Although PCBs are manufactured using computer-controlled machineries, there are times where they produce flawed end products. For instance, there are components that are misplaced or shifted place just before the soldering process.

Some of the flaws can also be caused by using too much solder paste, which could lead to solder leaks – these end up connecting adjacent circuit paths. Also, heating the solder too quickly can also cause one end of the component to lift up off the board and doesn’t make any form of contact. This phenomenon is called “tombstone.”

The Future of PCBs

Today, more and more electronic devices are being introduced to the market and each of them serves different functions. These new technological breakthroughs will push PCB manufacturers and experts to develop the industry in order to keep up with the growing trends in technology. As the trends in technology shift, printed circuit boards also shift in terms of design and performance.

The miniaturization of most electronic devices in the market also drive PCB manufacturers to create smaller and more compact boards but with increased capabilities. Some of the advancements in the industry is the use of three-dimensional or 3D molded plastic boards. It is also expected that integrated circuit chips will continue to flourish. These and other technological advancements will keep PCK manufacturing a dynamic industry for years to come.