8 Layer PCB  Stack Up 

8 Layers PCB Board

8 layers Printed circuit board is generally installed into compact devices that have very restrict requirements of spacing, such as laptop motherboard, communication backplane, wearable watch etc. Due to its complexity and high cost of manufacturing, your 8 layers PCB fabrication should be handled by a reliable and experienced manufacturer. RayMing particularly targets on high-end PCB Manufacturing and assembly services for 10 years and a variety of customers witness the good quality and outstanding services. Our advanced production lines and responsive team would make you stay comfortable without any hassle since you place the order to us.

8 Layer Prototype PCB

The 8-layered Prototype FR-4 PCB is a circuit board with 8 layers that are stacked firmly together with predefined and dependable mutual connections between the layers. An 8 layer FR-4 PCBs has more complex structure. Twisted Traces is a reputable name in the field of manufacturing 8 layer prototype PCBs.

1. It has multiple power and ground planes- a digital ground plane helps prevent noise coupling.
2. It provides more planes for shielding signals from other signals on adjacent layers
3. More layers aid in routing signals that need matching
4. For analog signals especially those with RF, isolation and impedance control on traces is needed.

8 Layer PCB Instant Quote

In terms of a custom printed circuit board, our 8 layer PCB Instant Quote is the fastest turn-time at the best price that we have to offer. For on-demand pricing and ordering for your next printed circuit board project,Get Fast Quote you can contact our online customer support , or send email to sales@raypcb.com , Get 8 Layer PCB Quote Now !

With the constant development in the electronics industry, there has been improvement in PCBs manufacturing. This development has pushed PCBs towards increasing demands such as high speed, reliability, miniaturization, and better functionality which lead to the fabrication of multilayer PCBs. Multilayer PCB are available in different layers which include 4 layers, 6 layers, 8 layers, 10 layers, etc.

These PCBs consist of prepreg and double-sided or single PCBs that are stacked together to produce multilayer PCBs via a predefined mutual connection between them.  8 layer PCBs have gained popularity in different fields due to their exceptional electrical and mechanical properties.  

What is an 8 layer PCB?

An 8 layer PCB is a type of multilayer PCB that provides ample routing space for applications that need multiple power islands. This printed circuit board can help to enhance EMC performance by the addition of two planes.

This board is often mounted on compact devices like motherboard, wearable watch, backplane, etc. The increase in the cost of 8 layers PCB justifies the cost increase to achieve great EMC performance. An 8-layer PCB stackup is made up of four planes and four wiring layers connected by seven rows of dielectric material.

This PCB features a six-layer board with improved EMC performance. An 8-layer PCB is sealed with a solder mask at the bottom and top.

An 8 layer stackup should follow this pattern;

• Signal 1
• Ground
• Signal 2
• Power
• Ground
• Signal 3
• Power
• Signal 4

Materials Used for Fabricating an 8-layer PCB

The type of material an 8 layer PCB stackup consists of determines its performance. Thus, you need to be careful when choosing materials during the production process. To produce high-performance PCB, the best materials are substrates and conductive materials.

Substrates

Substrates like glass-epoxy materials help to insulate heat and signals. This helps you to handle the stackup better even in applications with high temperatures. Substrate materials have a great glass transition temperature that maintains the solidness of the PCB stackup.

Conductive materials

Copper is the most effective conductive material utilized in the fabrication process of the layer stackup. This material is an ideal option since it is a good conductor of heat, allowing proper signal transfers and minimizing heat accumulation on the device. Copper is also a cheaper alternative to other materials like silver and gold which are very expensive.

Advantages of 8 Layers PCB Stackups

8 layer PCB stackups offer a number of benefits which makes them an ideal alternative to other circuit board materials. Below are the advantages of these PCBs;

Minimize vulnerability: 8 layers PCBs reduce the vulnerability of a device, hence, increase the overall performance. This helps to shield the internal layers from noise, thereby reducing its vulnerability to external forces.

Reduce Radiation: This type of multilayer stackup helps to get rid of any radiation that might occur in high-speed applications. Unlike other stackups, 8 layers PCBs get rid of electromagnetic interference radiation.

Reduce the cost of operation: 8 layers PCB stackups are a cost-effective option. As regards replacements and cleaning, this stackup saves a lot of money. This means that an 8-layer PCB stackup requires low maintenance and is very durable.

Increase functionality: Opting for an 8-layer PCB will help to improve the speed and functionality of the devices they are used for. This printed circuit board is more reliable and functional in different applications. This PCB features over 4 layers of conductive materials that enhance the signal traces.

Applications of the 8 layer PCB Stackup

The 8 layer PCB stackup is the commonest type of stackup used in most appliances. This multilayer PCB is functional in several applications such as;

• Medical industry
• Automobile industry
• Manufacturing industry
• Chemical processing industry
• Aviation industry

Factors that Determine the Cost of an 8 Layer PCB Stackup

The fabrication of an 8 layer stackup costs money and there are several factors that contribute to cost.  This type of multilayer PCB stackup goes for about $3, however, certain factors determine the price.

Size of the board: The printed circuit board’s size has to do with the components in it. When there are more components on the board, the size of the PCB will increase. An increase in size will result in an increase in the fabrication cost of the circuit board.

Type of finish: This is another factor that contributes to the cost of an 8 layer PCB stackup. There are several finish options, so the type you choose will determine the PCB cost. Finishes like HASL, ENIG, ENEPIG, and IMM Sn are some of the popular finishes available.

Thickness: The thickness of a circuit board has to do with the materials that enhance the strength of the board. The thicker a circuit board is, the higher its price. The type of materials used in designing the PCB can determine the thickness of the board.

Size of the holes: If the board requires more holes, the cost of design and manufacturing will increase. Thinner holes will require more work before the circuit board can be produced.

Custom specifications: If you request specific configurations for your PCB design, this will increase its cost. More demands for configurations and customizations often increase the cost of producing circuit boards.

Guidelines for a Standard 8-Layer PCB Stackup

It is important you understand that some guidelines need to be met to achieve better performance. If you want a board that delivers better performance, there are guidelines that help you achieve that.

Proper routing direction: For an 8 layer stackup, the application requirements determine the number of layers of signal layers. In a case where there are six signal layers, there must be a perpendicular routing for the signal traces on the adjacent layers. This helps to reduce crosstalk, signaling the significance of various signal routines on the layer stackups.

Ground planes alignment: When the ground planes are split it may result in discontinuity of impedance. The components on the external layer must have extremely low impedance. Also, the components must connect to the internal ground planes through the vias.

Proper return path: You must ensure that the return paths are short enough to eliminate interaction with other components on the PCB.

Buried or blind vias: Another option to consider is utilizing blind or buried vias which will maximize the available space for component routing.  You must ensure that you can place the blind via on the board.

The Designing Process of an 8 layer PCB Stackup

The design process of a standard 8-layer PCB starts with a working design. This means that you should determine the type of 8-layer stackup you intend to use. This process will help you achieve a good stackup.

Creation of Idea

First things first, you need to determine the type of 8-layer PCB you need. You can then look for the best way to ensure the PCB stackup works. Select designing software you can use in the designing process. After that, develop a schematic i.e the PCB blueprint.

After developing a schematic, you will add every single piece of information you want to the stackup. The designing process will start with a blank page on the designing software.

Inclusion of component

You will start the designing process by including all the required details on the stackup. Specify the stackup’s shape and the number of layers. Then, you will ink all the details on the schematic. Ensure you review all information on the design and change what is necessary.

Then, you must define the designing rules and be certain that you follow them in the designing process. Don’t take any of these rules for granted so that it won’t affect the stackup’s performance.

Placement of component: At this stage, you will have to determine where other components will be placed. You will also have to determine how to arrange the layers and position drill holes. After this, all the route traces on the stackup will be positioned and then add labels and identifiers. Doing all of these will help you produce the HDI PCB design.

Frequently Asked Questions

What type of vias can be utilized in an 8-layer stackup?

There are different types of vias you can utilize in this type of multilayer stackup. These vias include buried vias, through-hole vias, vias in pads, microvans, and blind vias.

What kinds of surface finishes can be applied on an 8-layer PCB stackup?

The kind of surface finish on an 8-layer PCB determines its performance.  Some surface finishes you can choose for your 8-layer PCB include; immersion silver, electroless nickel immersion gold, organic solder ability preservative, lead-free hot air solder level, etc.

Conclusion

In recent times, the 8-layer PCB stackup has become popular. It is important to know that the application of this multilayer stackup is increasing over time. Opting for an experienced 8 layer PCB manufacturer is vital. They will offer you the best stackups that suit your application requirements.

An 8-layer PCB increases the working speed of complex appliances. This stackup improves the signal integrity of various designs. The design of an 8 layer PCB might take some time due to its complexity. An 8 layer PCB manufacturer must be well-detailed to create a good design.