News & Updates

On interconnects, such as board-to-board connections or cascaded transmission line arrangements, you have an important EMC compliance metric that is sometimes overlooked. This is mode conversion, which can be visualized in an S-parameter measurement for differential and common-mode signal transmission. In this article, we’ll look at a short overview of mode conversion in high-speed design with some examples from common differential standards.

There are some aspects of PCB design and layout that seem deceptively simple, and yet they have a complex answer that is related to many important aspects of manufacturing. One of these design aspects is the match between PCB via size and pad size. Obviously, these two points are related; all vias have a landing pad that supports the via and provides a place to route traces into a via pad. However, there are some important sizing guidelines to follow when the matching pad and via sizes, and this match is an important element of DFM and reliability.

When you’re done creating a new board, it’s time to send your design data to the manufacturer. Before releasing your designs, you’ll want to make sure that everything is ready and works as intended. In this informative video, we’ll review some of the must-have checks before sending your output data for fabrication.

Are you looking for a free tool that you can use to calculate the impedance of differential microstrips? We created a simple tool you can use to calculate differential microstrip impedance for a given geometry and dielectric constant. If you’ve been looking for an accurate differential microstrip impedance calculator, then the calculator below is certainly one of the best free tools you’ll find on the internet before you start using field solvers to determine differential pair impedance.

In this article, we’ll discuss the key design features to implement, and steps to take prior to fabrication that will help prevent some common DFM problems. I’ll also provide examples of where I commonly see these PCB DFM problems in signal integrity circuits.

If you’re working with a high-speed digital component, there are some simple power integrity rules that should be followed. However, there is one quantity that is sometimes ignored when building a PDN impedance simulation: the spreading inductance of your plane pair. Here are some points designers should know about the spreading inductance of a plane pair.

In this article, I’ll present some design basics that every new designer should follow to help ensure their design process is successful. Some of these points may challenge the conventional view of how circuit boards are constructed, but they are intended to help balance low noise signaling, manufacturability, and ease of solving a layout.

The primary goal of your traces is to carry signals throughout your board without losses. To do this properly, you must familiarize yourself with the requirements for signals on the printed circuit board and how to optimize the topology of the board in terms of signal integrity. We will analyze the most popular routing cases applicable for using the Gloss and Retrace tools in Altium Designer to optimize your signal integrity.

High voltage PCBs are subject to certain safety and reliability concerns that you won’t find in most other boards. If your fabrication house specializes in high voltage PCBs and keeps materials in stock, they can likely recommend a material set, as well as a standard stackup you might use for certain voltage ranges and frequencies. If you need to choose your own materials, follow the tips below to help you narrow down to the right material set.

There are some guidelines I see many designers implement as a standard practice, often without thinking about it. Some of these practices are misunderstood or implemented without best practices. Others are implemented without thinking about the potential problems. One of these is the use of tented vias, which is sometimes implemented in a PCB layout by default. Is this always the right practice?

If you’re an antenna designer, then you’re likely familiar with all aspects of near-field vs. far-field radiation. Given the litany of radiated EMI problems that cause noise within and outside of an electronic device, one might suddenly realize their new product is acting like a strong antenna. To understand how EMI affects your circuits, it helps to understand exactly how near-field vs. far-field radiation from your PCB affects your ability to pass EMC checks and affects your circuits.

How often have you started down the PCB development process and been bogged down by time-consuming administrative tasks? Once you get ready for production, working through a design review and correcting any DFM problems takes its own share of time. With hastening product development timelines and shorter product life cycles comes the pressure to increase PCB prototype iteration speed without sacrificing cost or quality. So how can PCB design teams keep their development schedules on track without sacrificing quality or risking a failed prototyping run?

A journey of a thousand miles begins with a single step, or so the aphorism goes. I think it’s worth noting that the first step is the most difficult to take. Analysis Paralysis is especially true when dealing with a new software package, including the recent release of Concord Pro. The recent version has brought with it a deluge of interest and enthusiasm in such a phenomenal tool. But I must say, Altium hit this one out of the park.

When you need to pass EMC certification and your new product is being crippled by a mysterious source of EMI, you’ll probably start considering a complete product redesign. Your stackup, trace geometry, and component arrangement are good places to start, but there might be more you can do to suppress specific sources of EMI. There are many different types of EMI filters that you can easily place in your design, and that will help suppress EMI in a variety of frequency ranges.

Previously, I described the PCB fabrication operations relative to inner layer processing, lamination, drilling, and plating. The last step in the process is outer layer processing which is described below. Once the desired plated copper thickness of a PCB has been achieved, it’s necessary to etch away the copper between the features in order to define the outer layer pattern.

There are many factors at play in determining the impact of inductance on high-frequency power distribution systems. Two topic areas, inductance of the decoupling capacitor and inductance of the power planes, were addressed in earlier articles. This article will focus on the inductance of the capacitor footprint and via inductance from the capacitor footprint back to the PCB power planes.

High-speed buses, whether single-ended or differential, can experience any number of signal integrity problems. A primary problem created by propagating signals is crosstalk, where a signal superimposes itself on a nearby trace. The industry-standard PCB design tools in Altium Designer® already include a post-layout simulator for examining crosstalk. Still, you can speed up crosstalk analysis in parallel buses when you use a powerful field solver.

Any time-dependent physical system with feedback and gain has conditions under which the system will reach stable behavior. Amplifier stability extends these concepts to amplifiers, where the system output can grow to an undesired saturated state due to unintended feedback. If you use the right design and simulation tools, you can easily account for potential instability in your circuit models before you create your layout.

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.

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.