News & Updates
The concept of design variants entails taking a single PCB design, and then on the assembly side, modifying specific components used in the design. Either by not installing, not installing, or choosing alternate components as replacements on a specific assembly to ultimately create different end products. In that way, you could support multiple product lines. This article describes the approach to working with variants.
Before anything else, some advice. The revisions and lifecycle are an area that takes some planning. It used to be that Concord Pro was primarily for components, but now it has gone far beyond that. With the ability to store and manage many other items, including your various templates, projects, even PDF documents, not everything will have the same revision scheme. Concord Pro is so powerful that it can handle any revision scheme you’d want to set up.
Whether the board will be placed in a high pressure vessel or underwater, your design will need to withstand pressure to avoid failure. On the enclosure side, your vessel should be rated up to a certain pressure and may require frequent cycling to prevent implosion. On the electronics side, component selection and layout (especially at high voltage) become critical to preventing failure and ensuring reliability.
You need to define your PCB geometry in the context of your enclosure. If your board cannot physically be assembled into the final product, it doesn't matter how well laid out it is electrically. This webinar focuses on how the MCAD CoDesigner allows you to edit your PCB in the context of a higher-level assembly, allowing you to respect the relevant mechanical constraints.
The first update of Altium Designer 20.2 and Altium NEXUS Client 3.2 is now available. You can update through the Altium Designer update system ("Extensions and Updates") or download fresh builds from the Downloads section of the Altium website. Click on "Read More" to see a list of all changes in this update.
The history of engineering, both electrical and mechanical, is littered with approximations that have fallen by the wayside. These approximations worked well for a time and helped advance technology significantly over the decades. However, any model has limits on its applicability, and the typical RLCG transmission line model and frequency-independent impedance equations are no different. Copper foil roughness modeling and related transmission line impedance simulations are just one of many areas in which standard models cannot correctly treat signal behavior.
Once you’re planning for production of any new board, you’ll likely be planning a battery of tests for your new product. These tests often focus on functionality and, for high speed/high frequency boards, signal/power integrity. However, you may intend for your product to operate for an extreme period of time, and you’ll need some data to reliably place a lower limit on your product’s lifetime. In addition to in-circuit tests, functional tests, and possibly mechanical tests, the components and boards themselves can benefit from burn-in testing.
If you remember your days in school, then you probably remember the feeling of happiness and celebration when you pass a big exam. You’ll feel the same sense of adulation when your board spin passes a barrage of pre and post assembly tests, but a complex design might not reach that stage unless you implement the right design for testability methods. There are some simple steps that can help your manufacturer identify and quickly implement important bare-board and in-circuit testing (ICT), especially on critical circuit blocks.
This article describes the best hints and tips for designers of rigid-flex circuits. These tips include choosing the most appropriate material, suggestions for coordinating the PCB with the manufacturer, and a set of rules to be followed while PCB design.
There are a number of factors at play when it comes to the impact of inductance on high-frequency power distribution systems. This article will focus on the inductance of the capacitor footprint along with the inductance of vias from the capacitor footprint to the PCB power planes. Included are the various types and sizes of footprints for ceramic capacitors as well as a footprint for a tantalum capacitor; how changing the footprint impacts inductance and test results obtained for different capacitors.
In order to properly suppress common-mode noise, differential pairs must be routed in parallel, with perfect symmetry, and with matched lengths. In real PCBs, meeting these three objectives isn’t always possible. Instead of eyeing out your different pair lengths, the interactive routing tools in Altium Designer make differential pair length matching easy. You can encode permissible length mismatches as design rules as part of controlled impedance routing, or you can manually perform differential pair tuning using a variety of meandering styles. Here’s how this works in Altium Designer.
Augmented reality, virtual surgery, limb replacements, medical devices, and other new technologies need to incorporate haptic vibration motors and feedback to give the wearer a full sense of how they are interacting with their environment. Unless these cutting-edge applications include haptic vibration and feedback, users are forced to rely on their other four senses to understand the real or virtual environment.
Over the last 20 years, electronic devices have become increasingly sophisticated. Less than two decades ago, just having a mobile phone to make calls was rare; today, our phones power our lives. To meet the growing demand for smartphone technology, technology has become faster, more functional, and intuitive. Improvements to the component base have streamlined processes while reducing manufacturing costs.
You need to define your PCB geometry in the context of your enclosure. If your board cannot physically be assembled into the final product, it doesn't matter how well laid out it is electrically.
This webinar focuses on how the MCAD CoDesigner allows you to edit your PCB in the context of a higher-level assembly, allowing you to respect the relevant mechanical constraints.
Going deeper into crosstalk, there is always the issue of verifying EMI/EMC compliance through test and measurement. With the multitude of signal integrity problems that can arise in real PCBs, how can the astute designer distinguish them all? Some problems are clearer than others, with specific signal integrity measurements being developed for testing and measuring particular aspects of signal behavior. The fact is, multiple signal integrity problems could be present on a single interconnect simultaneously.
Once you’ve finished your new project and you’re ready to push it to your manufacturer, you’ll normally be stuck in an endless email chain with an engineer, or you’ll have to share cloud links with each other. The cloud sharing and design release tools in Altium Designer and Altium Concord Pro are a huge help in this area. In this post, I’m going to take an existing project I’ve worked with in a number of recent blogs, create some fabrication and assembly documentation, and finally push this data to a manufacturer using Altium Concord Pro.
To this day, I still see many PCB layout “rules of thumb” that first became common nearly 20 years ago. Do these rules still universally apply? The answer is a firm “maybe.” The discussion around PCB layout rules of thumb is not that these rules are correct or incorrect. The problem is that the discussion around these rules often lacks context, leading to the always/never type of discussion seen in some popular forums. My goal in this article is to communicate the context behind the common PCB design rules.
As the operating speed of components has increased, controlled impedance is becoming more common in digital, analog, and mixed-signal systems. If the controlled impedance value for an interconnect is incorrect, it can be very difficult to identify this problem during an in-circuit test. However, testing is normally performed on a PCB test coupon, which is manufactured on the same panel as the PCB. If you want to get through board spins quickly and aid future designs, you might consider designing a test coupon and keeping it handy for future designs.
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.