Nowadays, PCBS are very diverse in the electronics industry, but particularly popular are multilayer PCBS, which benefit from the many advantages of multilayer PCB boards. Although multi-layer PCB structure design and production requirements are high, and the higher the number of layers the more difficult to make, but the multi-layer PCB circuit boards are more and more popular, because many complex electronic equipment need multi-layer PCB to achieve its function. Do you know the advantages of multilayer PCBS? Let’s take a look.

What is a multilayer PCB?

A multilayer PCB is defined as a PCB made of three or more conductive copper foil layers. They look like layers of double-sided circuit boards, laminated and glued together, with layers of thermal insulation between them. All electrical connections between layers are achieved through holes such as electroplated through holes, blind holes and buried holes. This method can then be applied to generate highly complex PCBS of different sizes.

As time goes on, the functions of electronic devices gradually become more and more complex, requiring more complex PCBS. Unfortunately, PCBS are limited by issues such as noise, stray capacitance, and crosstalk, so certain design constraints need to be followed. These design considerations made it difficult to obtain satisfactory performance from single-sided or even double-sided PCBS – hence the birth of multilayer PCBS.

Multilayer PCBS are available in a variety of sizes and thicknesses to meet the needs of their extended applications, with variations ranging from 4 to 12 layers. The number of layers is usually even, as odd layers can cause problems in the circuit, such as warping, and are not cost effective to produce. Most applications require four to eight layers, but applications such as mobile devices and smartphones tend to use about 12 layers, while some specialist PCB manufacturers have the capacity to produce close to 100 layers or more.

Advantages of multilayer PCBS

Although multilayer PCBS tend to be more expensive and labor intensive to produce, multilayer PCBS are becoming an important part of modern technology. This is mainly due to the many benefits they offer, especially compared to single-layer and double-layer varieties. These advantages of multilayer PCB include:

• Smaller size

As electronics are becoming smaller and more sophisticated, PCBS are becoming smaller and smaller. One of the most prominent and acclaimed benefits of using multilayer printed circuit boards is their size. Because of the layered design of a multilayer PCB, it is reduced in size by increasing the number of layers, so it is itself smaller than other PCBS with similar functions. This brings huge benefits to modern electronics such as smartphones, laptops, tablets and wearables.

• Lighter weight

As PCBS get smaller, component sizes get smaller. The multi-layer PCB design eliminates the multiple connectors required for single – and double-layer PCB interconnections, thus reducing weight. So it’s a good option for small electronic devices where weight is a concern.

• Higher durability

Multilayer PCBS tend to be durable due to their nature. Having more layers tends to mean that the board is thicker and therefore more durable than single-sided PCBS. This is another reason that adding functionality through additional layers is better than increasing the size of a single layer. This enhanced durability means that boards can withstand harsher conditions and often last longer.

• More powerful

Multilayer PCBS are extremely high-density components that combine multiple layers into a single PCB. The use of multilayer PCB is not only convenient for wiring, but also shortens the length of wiring. These proximity also makes the boards more connected, and their inherent electrical properties allow them to achieve greater capacity and speed.

• Superior quality

Multilayer boards require more planning and intensive production processes, so they are generally of higher quality than other types of boards. Designing and producing these boards requires more skill and more advanced tools than simple components, thus increasing the possibility of obtaining a high quality product. Many of these designs include complex controlled impedance characteristics and electromagnetic interference shielding, further improving performance.

• Single connection points

Multilayer PCBS are designed to be used as single units rather than in series with other PCB components. As a result, they have a single connection point instead of the multiple connection points required to use multiple single-layer PCBS. This also proves beneficial in electronic product design, since they only need to include a single join point in the final product. This is especially useful for small electronics and gadgets designed to minimize size and weight.

Disadvantages of multilayer PCB

Multilayer PCB has many advantages and is suitable for various advanced technologies. However, these types of PCBS are not suitable for all applications. In fact, some of the disadvantages of multilayer PCBS may outweigh their advantages, especially for lower cost and less complex electronic devices. These disadvantages include:

• More Expensive

It is more expensive to build a board with more layers than one or two. This requires more time and skill, which increases the cost. The design and production of multilayer board is more complicated than that of single layer board. This requires highly skilled designers and manufacturing professionals familiar with specialized equipment.

• Greater production limitations

Multilayer boards are more challenging to produce and provide reliable services because they require specialization. Finding the right company to design, manufacture or repair multilayer boards can be difficult. Finding someone who can repair the boards can be more challenging. Therefore, before deciding on a PCB manufacturer as a contract manufacturer, it is a good idea to ask the PCB manufacturer carefully about its capabilities in multi-layer PCBS.

• Longer production times

As complexity increases, so do manufacturing requirements. This plays a key role in the turnover rate of multilayer PCBS – each board requires a large amount of time to produce, resulting in more labor costs. Rework can take a long time if you make a mistake or want to make changes during production. You may need to replace parts or increase the cost of materials.

• More complex maintenance

Because of the complexity of multilayer PCBS, they are more prone to failure. Assuming an electronic component fails or the board is physically damaged, it can be challenging to detect problems if the layers of the board and the through-holes connecting them are not visible from the outside. Due to the large number of components, repairs are more complex and take longer.

Is the performance of PCB multilayer better with more layers?

The performance of PCB is not equal to the number of layers, simple four or six layers of PCB, also have excellent performance. In fact, the number of PCB layers is only a rigid requirement of PCB design, not as a standard to judge the quality of PCB.

The more PCB layers, the higher the wiring difficulty index, so the production cost is relatively high. However, this does not mean that the performance of multi-layer PCBS is better than that of PCBS with fewer layers.The high level PCB is only to allow the electronic circuit to obtain more wiring space, to ensure that the wiring of the fine points can also have the optimal layout. The higher the number of PCB layers, the lower the electromagnetic interference between the layers, thus reducing the interference between signals, so that the service life of the PCB is extended.

Due to the different technical capabilities of each PCB factory, each layer can reasonably accommodate the total number of components is not the same. Theoretically, within reason, there is no difference in performance between putting 100 components on one layer of PCB and spreading them on two layers of PCB. However, due to the smaller and smaller volume demand of current electronic products, it is necessary to reduce the design space and the volume of PCB under the same performance condition.

Conclusion

These shortcomings of multilayer PCBS are easily addressed if carefully designed and manufactured. These multilayers are certainly popular. They are used in computers, laptops, mobile phones, tablets, medical devices, GPS trackers and many other more complex circuits and devices. In general, multilayer boards tend to be of higher quality than standard PCBS because they require more design, planning, and investment. The price may be higher, but the features and performance make up for it.

Whatever your product goal, tdt-ele can help you meet your needs through multilayer printed circuit boards or other manufacturing options.