Often, the design and manufacturing of a printed circuit board (PCB) is as critical as the design of the main circuit itself. Manufacturers are further making use of compact, flexible PCBs to assemble and organize electronic circuits. A PCB could comprise one or more insulating boards on which copper layers and conductive signal traces have been either etched or printed. Depending on the complexity of the circuit, printed circuit board manufacturing could possibly involve anywhere from a single layer PCB to eight (or more) layers.
This article discusses the types of PCBs based on the number of layers and their rigidity.
Types of PCBs based on layers
If you have a very basic circuit, your PCB manufacturer will likely recommend the use of a single-sided PCB. This is the least complex PCB of all as the entire circuit-comprising the electrical components and the copper traces-is contained on a single insulating board.
A double-sided board holds a circuit that is slightly more intricate than a single-sided board. As the name suggests, both sides of the substrate are used for housing the circuitry components. Through hole technology is often utilized when manufacturing PCBs that are double-sided or multilayered.
Complex printed circuit board manufacturing is accomplished via multi-layered PCBs that comprise multiple sheets of substrate with insulating layers in between each. Depending on the complexity of a circuit, such PCBs could range from 2 layers to 4 layers to 8 layers, going right up to even 42 layers in highly sophisticated circuitry.
Types of PCBs based on rigidity
Different applications need different types of PCBs. For instance, a rigid PCB is most prevalent and can be found in daily-use consumer electronic items such as computers, televisions, mobile phones and so on. Such a board, when bent beyond a certain limit, will crack or break. The other common type of PCBs that are offered by a PCB manufacturer is the flexible PCB. The circuits in such a PCB are assembled on a thin, flexible insulating material. This allows the PCB to be bent and curved as desired without causing damage to the circuit or the insulating material. You might see flex PCBs being used in medical equipment, flexible heaters, or even equipment such as hearing aids.
The rigid-flex variety of PCBs is a combination of rigid and flexible PCBs. These circuits are used in aerospace and military applications, where a very dense circuit is required. Rigid-flex PCBs help save a significant amount of space, resulting in electronic products that weigh much less.
Printed circuit board manufacturing can be carried out for a limited number of circuits or for large-volume production. It is essential to choose a PCB manufacturing firm with a proven track record.