PCB layout is the same thing as finalizing some piece of art. Engineers may spend days, weeks, or even months attempting to design these patterns to develop something unique. But just like these engineers do, wouldn’t you want to do as they do and turn all the electrical theories that you’ve learned into something real?
Of course, you would. First, you may want to understand a few things concerning the PCB layout process. While challenges lie ahead, PCB layout is the best part when it comes to designing a PCB.
- 1. What is PCB Layout?
- 2. PCB Layout Design
- 3. The Process of Considering PCB Layout/PCB Layout Guidelines
- 4. PCB Layout - Three Elements of EMI
- 5. PCB Layout Services
- 6. How to go About Designing a PCB Layout
- 7. PCB Layout Software
- 8. RF PCB Layout
- 9. PCB Layout-How it Can Save You Time and Money
1. What is PCB Layout?
First, a layout is how components of something get arranged or how materials get set. The same is true when it comes to PCBs. A PCB layout is a broad term indicating several processes required in designing a PCB. It involves making traces, mounting holes cutouts, labeling, and specifying component locations, among others.
(human hand drawing of a PCB layout)
2. PCB Layout Design
PCB layout design is a unique skill that demands the comprehension of both the PCB CAD system and PCB design software. The following are some of the essential aspects here:
2.1 The principle of the original layout
Almost all PCB design software has the option of “auto-router,” and most of the time, many designers would immediately take the chance of using it. The reason is that it’s an easy way of routing a PCB. But to be on the safe side, it’s advisable never to use it. The reason is that it’s not as precise and symmetrical as it should be.
2.2 Original layout direction
Before you can begin placing components, you need to consult your producer first. You may have to listen to any demands that he may have, such as the number of layers they can handle. Other requirements may include things such as minimum trace widths and trace spacing, among others.
2.3 The spacing of originals in the layout
When electricity passes through the copper traces, it will generate heat. But such is avoidable by controlling the spacing of the marks. Their width needs management. It is important to note that more comprehensive traces mean less resistance than the current encounters as it passes through the circuit.
2.4 Avoid using a 90-degree angle
It’s advisable to avoid the use of a 90-degree tracing angle but instead to use 45 degrees. But what’s the reason for this? 45 degree tracing aspects prevent short circuits. 90-degrees angles may also not etch fully, and this may cause short courses.
2.5 Always create a plane
It would help if you always had a common ground terminal in the circuit schematics. Such is essential for a PCB layout as it provides traces with a standard reference aimed at measuring voltages. Problems arise when you attempt utilizing marks as opposed to ground planes for routing.
2.6 Avoid overlapping
Finally, at all costs, ensure that you avoid issues to do with overlapping when it comes to PCB layouts. Such can make the entire line even more complicated.
(a virtual PCB layout design of a circuit board)
3. The Process of Considering PCB Layout/PCB Layout Guidelines
While PCB layout may seem like a piece of art, it’s essential to start in an organized manner. To come up with the best design, you need to adhere to the following necessary three steps.
Step 1: First, you need to turn your schematics into a form of PCB layout.
Step 2: Secondly, you need to add and subsequently rotate the components to reduce the air wires’ lengths and crossing.
Step 3: Finally, adjust the layout size for routing.
(An engineer working on a PCB layout and finished design)
4. PCB Layout - Three Elements of EMI
Electromagnetic interference (EMI) is caused either by an electrical or electronic device or through electromagnetic fields. EMI is a common phenomenon in PCBs. The following are three elements of EMI:
4.1. Three types of coupling
Conducted coupling happens if the energy source energizes a decent part of the antenna that concerns the other.
- Electric field coupling – this is a coupling that’s energized or driven by voltage. To put it in other words, it is proportional to the energy of the source.
- Magnetic field coupling – this is the coupling energized or driven by the current. It is equivalent to the flow of the source, put in other words.
Clock circuit - on a PCB, synchronous digital circuits are commonly the most reliable signals. Therefore, at narrow bands, it is possible to observe radiated emissions. Also, these peaks tend to take place at the harmonics of the frequency of the clock. Plenty of PCBs don’t have clock signals in them but rather have some digital information.
4.3. Power switch circuit
Switch-mode power supplies and DC converters provide several voltage levels by rapidly switching voltage levels in a transformer. If you happen to be keen enough, you’ll notice that the typical switching frequency stands between 10-100 kHz.
5. PCB Layout Services
Are you in the market for producers that offer excellent PCB layouts services? If you happen to be a beginner in this field, then here are some of the most important things that you need to consider:
5.1 PCB Layout Designers’ Services
If you plan to acquire PCB layout services, you must ensure that you are getting such services for existing and new PCBs. Besides tests, ensure that your manufacturer adheres to height, size, and weight issues, especially if the PCB layout seems challenging to you.
(when sourcing for PCB layouts, work with a designer that does tests to their plans and final boards)
5.2 PCB Layout Designers’ Deliverables
When working with designers, you will see the following deliverables:
- PCB layer stack diagrams
- Complete schematics
- Full Gerber files
- Plenty of software
5.3 The Importance of PCB Layout Services
Technical Competency – having access to an expert comes with a more significant advantage when designing PCBs.
- Streamlined Process – with PCB layout services, there’s a chance to detect errors and improve products before marketing.
- Better quality – undoubtedly, layout services come with better quality due to competition.
- Fast Turnaround Time – with a specialist, rest assured of PCBs’ production on time based on their careful planning.
- Cheap – this is simple. It’s cost-effective to outsource than undertaking manufacturing by yourself.
6. How to go About Designing a PCB Layout
In its basic form, a PCB layout means transferring a circuit from a breadboard to become a permanent and stable physical form. Creating a PCB layout involves the following:
6.1 The Schematics
A schematic is a diagram of components, circuits, and connections laid out that’s easy to follow. When designing PCB layouts, it’s always essential for you to begin with schematics. Schematics help with constructing and understanding the system of circuits.
6.2 High-frequency signals
PCBs that tend to support high-frequency signals demand special requirements. Many of the interfaces used today operate at more than 50 MHz, meaning that some knowledge on how to go about avoiding issues to do with high-speed signals is essential. At high frequencies, the PCB layouts are all about understanding the physics of electrons flow.
6.3 The Routing of Signal and Placement of Components
When it comes to signal routing and the placement of components, all you need to know is where the signal and currents will flow on your PCB. You need to keep your digital signals as far away from the analog signals. Analog circuits tend to be sensitive to digital signals, which can introduce noise in the analog side.
6.4 A work of art and science
With technology continuing to advance at unprecedented speeds, the frequency of signals has become blazing fast. Therefore, the need to understand signal propagation is a big necessity. There’s a need to close the gap between analog and digital designs. Both disciplines overlap noticeably at very high speeds, making them both an art and science.
(the interface to expect with the PCB layout software)
7. PCB Layout Software
The following are some of the most common PCB layout software:
- Autodesk Eagle – this is one of the well-known schematics and PCB design software so far. It contains a schematic editor aimed at designing diagrams and a PCB layout editor.
- KiCAD – this is a cross-platform and open-source electronics automation suite. It includes a PCB editor for producing professional PCBs and a schematic editor for editing and creating schematic designs.
- Fritzing – this is the same as KiCAD. It includes a schematic, a breadboard layout, and a PCB view.
- DesignSpark PCB – this one provides an easy-to-learn environment consisting of schematics capture and a PCB layouts tool.
- EasyEDA – this one provides one of the most potent schematics captures and consists of a library designer, a PCB editor, and a project management tool.
- UpVerter – this is the same as EasyEDA. It enables hardware engineers to create, share, and review PCBs and schematics.
- PCBWeb Designer – this is a free CAD application aimed at designing and producing electronics. It consists of schematic capture and an integrated arrow parts catalog.
- ExpressPCB Plus – this is an EDA software aimed at creating and subsequently designing electronics circuitry.
- TinyCAD – this is an open-source software project that supports custom and standard symbol libraries. It supports PCB layout programs consisting of several formats.
- Osmond PCB – this is an only MAC-based EDA tool that supports schematic capture and PCB layouts design.
7.1 free PCB layout software
From the above list, the following are the open PCB layout software:
8. RF PCB Layout
RF PCBs are an exciting and growing sector across the PCB industry. They are also involved with a wide range of options, and RF PCB layouts demand precision and accuracy.
PCB industry, any frequencies above 100MHz plate deemed RF PCB. The microwave PCB is about 2GHz, and RF PCB design is usually a 2-layer or 4-layer board. Component arrangement requirements will be more stringent, so professional PCB layout design knowledge is needed.
(RF electronic component)
9. PCB Layout-How it Can Save You Time and Money
When it comes to the design and manufacture of almost everything, having a functional layout is essential. Likewise, in PCBs production, having a good structure in place brings about the desired results. However, there are a few issues that concern the PCB layouts, as highlighted below:
9.1 Problems That Arise From a Lack of PCB Layout Preparation
Without efficient and accurate PCB layouts preparation, there’s a massive chance of total board failure. Others include reworks and limited functionality.
9.2 How PCB Designers Can Meet PCB Layout Preparation Demands
It’s simple. All that’s needed is to use essential tools such as DFM software and PCB design tools.
9.3 PCB Layout Preparation Considerations
Some of the essential considerations include the shape and size of the PCB. Also, manufacturers need to be keen when it comes to space considerations.
9.4 Complex PCB Layout Preparation Issues
Producing a PCB is not an easy process. Complex PCB layouts preparation issues include creating the best layout between traces, trace widths, and other factors that may affect board functionality.
9.5 How to Solve Plenty of PCBs Layout Preparation Problems
To solve layout preparation problems, all you have to do is employ sophisticated computer-aided design or computer-aided manufacturing.
(A complete board that has undergone the best layout practices)
PCB layouts are essential for proper board functionality. Are you having a tough time undertaking your board layout? If so, let us at OurPCB assist you. We manufacture PCBs under the best layout plans. We understand the importance of PCB layouts, meaning that our boards will function as intended.