If you want your printed circuit board designed correctly, the best way would be to employ the services of a power electronics design company. However, some people prefer to do it on their own, and there’s no problem with that either. This article covers everything you need to know about the basics of PCB design, including a comprehensive step-by-step guide, best practices, and more.
What’s a PCB?
A printed circuit board (PCB) is a flat plate or base composed of insulating materials. These flat plates have a pattern of conducting components—some are easy while others are more complex. Nevertheless, the first phase of every PCB is its design.
You may be wondering, “why is it so important to understand the basics of PCB design?” Undergoing several revisions can be expensive, not to mention that it can significantly delay your project from being completed, taking up more of your time than initially anticipated.
The best way to minimize mistakes and ensure you have a cost-effective product that works is to work alongside seasoned engineers.
10 Steps to Help You Design Your Own PCB
Designing your own PCB may be complex for some, but we’ve simplified the process as much as possible.
Fully Grasp the Electrical Parameters of the System
Before you get started, the first thing you need to do is understand and familiarize yourself with the system’s electrical parameters. This includes the following:
- Current maximums;
- Types of signals;
- Capacitance limitations;
- Impedance characteristics;
- Shielding considerations;
- Type of circuit components and connectors and their locations; and
- Detailed net wire listing and schematic.
Create the Schematic
After understanding the first step, the next phase is to create a schematic. This refers to the PCB’s design at the electrical level, where you consider its purpose and function. In other words, this phase doesn’t show the mechanical representation of the PCB yet.
Create the PCB Layout
With the help of a PCB provider, you can move on to the next step. The PCB provider will work alongside principal engineers to help create a schematic using software such as Altium and Allegro. These software platforms will help you visualize how your PCB will operate and the placement of the various components. After creating the schematic, a mechanical engineer will ready the design and show you how everything fits in the device the PCB is intended for.
Design the Stackup
Designing your PCB stackup is crucial in the early stages of this project, mainly because you have to consider impedance. Impedance is about how quickly and how much electricity travels through a trace. The stackup has a significant role in this entire process because the mechanical engineer uses it to design the PCB and see how it fits into the device it’s for.
Consider the Design Rules and Standards
This phase of the PCB design process primarily deals with the IPC’s standards and acceptability criteria. The IPC is the industry association that deals with manufacturing PCBs and other electronics. IPC’s standards provide you with all the information you need to know about manufacturing PCBs. That’s why you must choose a PCB layout provider who’s already familiar with these standards to minimize any delays or revisions as much as possible.
Put In the Different Components
Typically, you’ll have a lengthy discussion with your PCB provider regarding the design and layout guidelines, allowing you to plan out where you want to place the components. For instance, the standards may indicate that specific components shouldn’t be placed near others to avoid electrical noise or other similar disturbances. Your PCB provider should have data on each component present. After placing these components on the mechanical layout, the PCB provider will send the layout to you for approval.
Put In the Drill Holes
The components and a connection primarily drive this phase in the PCB design process. Many flex circuits available are typically double-sided. In other words, these circuits are connected to the drill hole located on the bottom layer.
Route the Traces
The next step is to route the traces, which involves connecting the different segments.
After doing the last step, you can add labels, markings, or identifiers to the layout. This step is crucial because it can help determine which components go where.
Generate the Design or Layout
Finally, the last step is to generate your design or layout files. These files will have all the data needed to create your PCB. Once you’ve generated them, you can now start the manufacturing and assembly process of your PCB.
Best Practices When Designing a PCB
When designing a printed circuit board, you shouldn’t do whatever you feel like doing—there are some best practices you’ll want to keep in mind to make the entire process easier and more seamless. For one thing, it’s vital to have open and regular communication with the PCB or flex application engineer, especially during the early phases of the design process. This way, you can discuss everything that needs discussing for your project, such as the requirements. Communicating with your PCB provider also ensures that you understand each other and are on the same page. This reduces the likelihood of extensive revisions in the long run.
Of course, it’s unheard of for a PCB design to be 100% perfect on the first go. However, constant communication with the right people will help ensure that your printed circuit board is correctly designed from the get-go. If there are any revisions you need to make, they’ll most likely be minimal changes and won’t significantly push back your project’s timeline.
Composition and Materials Needed
Flex circuits typically use a copper-clad substrate or polyimide-based film, while rigid-flex uses FR4 or an FR4 stiffener. With an FR4, you can quickly build up layers while creating technology content.
Among other things, you can also expect to use a solder mask. This is a common technique wherein the circuit board is covered with an epoxy-based LPI or cover coat for flex, excluding some components that should be soldered and the gold-plated terminals.
Hopefully, this article covered all the information needed for designing a PCB. Of course, it’s always best to rely on professionals when creating something like this, but the steps above are a good starting point for those who want to do it on their own.