Getting started for the first time in a new project can be difficult. Chicks probably do not appreciate being pushed out of the nest, and teens are nervous before their first date. I was scared to death on my first date. However, I am happy to have taken this first step because this appointment was one of the great moments of my life.

You end up now at an equally important moment, namely designing your first multilayer printed circuit board. Are you concerned about not making mistakes? If so, do not worry. You are not different from others, and we have some information to help you. We will talk about some of the issues that need to be addressed about libraries, as well as some general design principles.

Sometimes, before you reach the goals you set for yourself, you must take a step into the unknown to give yourself courage. The design of your first multilayer board is one of those "leaps in the dark" for a PCB designer. Let's jump together and find out how you can make a good start for this type of design.

Make sure your library is configured for multilayer designs
The first thing to determine when designing multilayer printed circuit boards is your CAD library. If you have previously only designed single or double-sided cards, your library may not be set up for multilayer configurations. Here are three areas to consider:

Negative Plan Layers: Negative image plan layers are often used to create ground and power planes on multilayer printed circuit configurations. Some CAD tools require spacings to be embedded in pellet and footprint shapes for holes drilled in a negative plane layer. If you use one of these tools, make sure that your pellet and fingerprint shapes are configured with good spacings for the negative plane. If your shapes are not configured for these gaps, a short circuit will occur.

Pad shapes on internal signal layers: Some designs use different forms of pellets on the outer layers compared to the inner layers. For example, 1-pin pellets often have an easily identifiable square shape, instead of a round shape normally reserved for the inner layers. If your libraries are not configured for multilayer configurations, you may not get the desired pellet shapes on the internal signal layers.

Drawing parts: If you create your manufacturing and assembly drawings in your routing tools, you will probably have different logos, views, and tables saved in your library. These will need to be modified for multilayer cards.

3D image of a panel of components of a circuit board
Make sure your library components are configured for multilayer printed circuit design.

Understand the requirements of manufacturing
Multilayer printed circuit design has several more important advantages than single or double-sided board design. Not only will you be able to save space and increase the density of your design, but you'll also have better control over signal integrity issues. The solution is to prepare everything before the design arrives in production so that you understand the requirements of the manufacture of multilayer designs before starting your project.

Manufacturing has different requirements depending on the technological level of the card. Some shops may not be configured for making cards with a small number of layers or with very few leads and small spacing widths. If you exceed these limits, your manufacturing costs may increase, or your card may not be manageable.

Take the types of via for example. In general, manufacturing workshops run ordinary through vias, but you must first consult them before using buried vias, blind, or micro vias. And as we mentioned, you also have to deal with the members of the workshop about the width and spacing of the tracks, the amount and the configuration of the layers of the map. All of these factors can affect the fabricability of the PCB, and we advise you to fully understand all of these factors before you begin your design.

Tips for designing multilayer printed circuits
Now that your library is set up and you have previously consulted the manufacturing shop, you are now ready to create your multilayer PCB design. Here are some tips you probably do not know about the multilayer card design:

Route the adjacent signal layers in opposite directions. If you have adjacent signal layers on layers 2 and 3, route one horizontally and the other vertically. This will prevent crosstalk problems.
Use diapers for power and mass plans. This will not only allow you to distribute your power and mass evenly, but it will also create a microstrip structure that will ensure signal integrity.
Reduce the size of the through-pads of the inner signal layer. Verify that the fabrication shop accepts small inner layer pellets for components and through vias. If so, the smaller size of the pellets will open more routing channels.

Taking the first steps in multilayer printed circuit design may seem impossible. Although it is not as intimidating as the first outing of the nest for a chick or a first date, the feeling is close to it. We hope these tips will help you lighten the load on your shoulders and take off.

The use of high quality printed circuit design software, such as Altium Designer and Altium's CircuitStudio, can also help you realize your next circuit board routing project. Altium Designer includes all the features that will help you create library components, manage your layer structures, and position and route complex multilayer map designs.

Would you like to know more about Altium's solutions for designing your next multilayer PCB multilayer PCB ? Or Do you need multilayer PCB? All of them you can find on online.

Author's Bio: 

Beethy