News & Updates
S-parameters are fundamental quantities in signal integrity, and an ability to understand them from measurement or analysis is very important. If you have a 3-port network, like a power divider or circulator, it may appear that you must use a 3-port VNA to measure these S-parameters. It is always acceptable to measure between two ports, but you need to know what exactly it is you are measuring. In this article, we’ll look at the relationship between the true 3-port S-parameters with a 2-port measurement.
Before implementing design for manufacturing, it is important to understand the underlying process behind producing a physical PCB. Regardless of the various technologies present in each facility, a large majority of industry-leading manufacturers follow a specific set of steps to turn your design from a drawing in a CAD application into a physical board. In this article, we'll cover the basics that designers need to know as part of our crash course series on PCB manufacturing.
If you compile a list of skew sources, you'll see that fiber weave-induced skew is only one entry on a long list of skew sources. We'll look at this list of possible skew sources below, and we'll see how they affect the operation of your PCB. From the list below, we'll see that some of these issues with skew are not simply solved by paying attention to the fiber weave construction in a PCB substrate.
This track is for the engineer who understands high-speed design requirements and wants to learn design practices to help ensure signal integrity and EMC with fast digital protocols, mixed-signal boards, and high layer counts.
We love answering questions from our readers and YouTube viewers, and one of the recent questions we received relates to EMI from switching elements in a switching regulator is "Should a cutout be placed below the inductor in a switching regulator circuit?". Despite the variations in inductors and their magnetic behavior, there are some general principles that can be used to judge the effects of placing ground near inductors in switching regulator circuits. We’ll look at some of these principles in this article
We are happy to announce that the Altium Designer 22.6 update is now available. Altium Designer 22.6 continues to focus on improving the user experience, as well as performance and stability of the software, based on feedback from our users. Check out the key new features in the What's New section on the left side of this window!
Find 9 mistakes in a PCB design and get added into the lucky draw to win a prize from Altium!
Now you can assess your library’s health at a glance with the Library Health dashboard, view and share your bill of materials (BOM) and view and download PDF documents, all in your web browser. We improved the existing diff and compare features, and released a new version of MCAD CoDesigner. Register for the webinar to learn more!
This Semi-Additive Process is an additional tool in the PCB fabricators' toolbox that enables them to provide feature sizes for trace width and spacing that are 25 microns, (1 mil) and below depending on the fabricators' imaging equipment. This provides much more flexibility to breakout out tight BGA areas and the ability to shrink overall circuit size and/ or reduce the number of circuit layers in the design. As the PCB design community embraces the benefits of this new printed circuit board fabrication technique, there are of course many questions to be answered.
It’s no secret that component shortages have become more frequent this year. In fact, countries around the world are losing billions in revenue due to supply issues. Having the right components on hand is more crucial than ever as availability, obsolescence, counterfeit products and environmental non-compliance risks continue to grow. Fortunately, many shortages can be avoided by introducing proactive supply chain practices.
When some designers start talking materials, they probably default to FR4 laminates. The reality is there are many FR4 materials, each with relatively similar structure and a range of material property values. Designs on FR4 are quite different from those encountered at the low GHz range and mmWave frequencies. So what exactly changes at high frequencies, and what makes these materials different? To see just what makes a specific laminate useful as an RF PCB material, take a look at our guide below.
In today’s fast-paced world where iterations of electronics are spun at lightning speeds, we often forget one of the most critical aspects of development: testing. Even if we have that fancy test team, are we really able to utilize them for every modification, every small and insignificant change that we make to our prototypes? In this article, we will review a very low cost, yet highly effective and quite exhaustive test system that will get you that bang for your buck that you’ve been looking for.
If you’ve ever looked at the BOM for a reference design or an open-source project, you may have seen a comment in some of the entries in your BOM. This comment is either “DNP” or “DNI”. If you think about it, every component placed in the PCB requires some level of placement and routing effort, which takes time and money if you’re working for a client. This begs the question, why would anyone design a board with components they don’t plan to include in the final assembly?
When it’s time to share your design data with your manufacturer, it’s like taking a leap of faith. Sending off a complete documentation package might seem as easy as placing your fab files in a zip folder, but there are better ways to ensure your manufacturer understands your project and has access to all your design data. For Altium Designer users, there are multiple options for creating and packaging release data into a complete package for your manufacturers.
If you’re designing a circuit board to be powered by anything except a bench-top regulated power supply, you’ll need to select a power regulator to place on your board. Just like any other component, your regulator has stated operating specs you’ll see in a product summary, and it has more detailed specs you’ll find in a datasheet. The fine details in your datasheets are easy to overlook, but they are the major factors that determine how your component will interact with the rest of your system.
It would be nice if the power that came from the wall was truly noise-free. Unfortunately, this is not the case, and although a power system can appear to output a clean sine wave, zooming into an oscilloscope trace or using an FFT will tell you a different story. When you take "dirty" power, put it through rectification, and then pass it through a switching regulator, you introduce additional noise into the system that further degrades power quality. If you’re a power supply or power systems designer, then you know the value of supplying your devices with clean, noise-free power.
If you’re an electronics designer or you’re just beginning your career as an engineer, the PCB stackup is probably one of the last things you’ll think about. Simple items like PCB copper thickness and board thickness can get pushed to the back burner, but you’ll need to think about these two points for many applications as not every board will be fabricated on a standard 1.57 mm two-layer PCB
I often get questions from designers asking about things like signal integrity and power integrity, and this most recent question forced me to think about some basic routing practices near planes and copper pour. "Is it okay to route signal traces on the same layer as power planes? I’ve seen some stackup guidelines that suggest this is fine, but no one provides solid advice." Once again, we have a great example of a long-standing design guideline without enough context.
Electronics schematics form the foundation of your design data, and the rest of your design documents will build off of your schematic. If you’ve ever worked through a design and made changes to the schematic, then you’re probably aware of the synchronization you need to maintain with the PCB layout. At the center of it all is an important set of data about your components: your schematic netlist. What’s important for designers is to know how the netlist defines connections between different components and schematics in a large project.
There are plenty of PCB manufacturing services you can find online, and they can all start to blend together. If you’re searching for a new service provider, it can be hard to compare all of them and find the best manufacturer that meets your needs. While experienced designers can spot bogus manufacturers from afar, there is always a temptation to go with the lowest priced, supposedly fastest overseas company you can find. However, there is a lot more that should go into choosing a PCB manufacturing service than just price.
Pi Filters are a type of passive filter that gets its name from the arrangement of the three constituent components in the shape of the Greek letter Pi (π). Pi filters can be designed as either low pass or high pass filters, depending on the components used. The low-pass filter used for power supply filtering is formed from an inductor in series between the input and output with two capacitors, one across the input and the other across the output. Keep reading to learn more about their application in the PCB Design.
The first question that should come up when selecting materials and planning a stackup is: what materials are needed and how many layers should be used? Assuming you’ve determined you need a low-loss laminate and you’ve determined your required layer count, it’s time to consider whether you should use a hybrid stackup. There are a few broad situations where you could consider using a hybrid stackup with low-loss laminates in your PCB
Batteries offer a great power source for electrical devices that need to be mobile or located somewhere where connection to a mains electricity supply or other power source is impossible. The biggest problem with battery power is the expectation of users that the device will operate for significant periods with the need for recharging or replacing the batteries. This demand is placing the onus on the designer to improve efficiency and reduce power demand to meet this need.
A number of us on this blog and in other publications often bring up the concept of target impedance when discussing power integrity in high-speed designs. Some designs will be simple enough that you can take a “set it and forget it” approach to design a functional prototype. For more advanced designs, or if you’re fine-tuning a new board that has existing power integrity problems, target impedance is a real consideration that should be considered in your design.
Dual power supplies are circuits that generate two different output voltages from a single input source. The simplest method of generating dual output voltages is to use a transformer with two taps on the output winding. Bespoke transformers can have any voltage ratio depending on the number of windings in each part of the output side of the transformer.
With digital boards that are nominally running at DC, splitting up a power plane or using multiple power planes is a necessity for routing large currents at standard core/logic levels to digital components. Once you start mixing analog and digital sections into your power layers with multiple nets, it can be difficult to implement clean power in a design if you’re not careful with your layout.