Last updated on Apr 4, 2025

What are the most common SI and PI mistakes and misconceptions in hardware development?

If you are a hardware developer, you know how important it is to ensure the quality and reliability of your designs. However, you may also encounter some common challenges and misconceptions when it comes to signal integrity (SI) and power integrity (PI), two critical aspects of hardware development. In this article, we will discuss what SI and PI are, why they matter, and how to avoid some of the most frequent mistakes and myths that can affect your hardware performance.

1 What is SI and PI?

SI and PI are two terms that describe the behavior and interaction of signals and power in a hardware system. SI refers to the ability of a signal to maintain its shape, timing, and voltage levels as it travels along a transmission path, such as a trace, a cable, or a connector. PI refers to the ability of a power supply to deliver stable and clean voltage and current to the components that need it, such as ICs, sensors, or LEDs. Both SI and PI depend on the physical characteristics of the hardware, such as the layout, the materials, the impedance, the parasitics, and the noise sources.

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2 Why do SI and PI matter?

SI and PI matter because they affect the functionality, performance, and reliability of your hardware. If you neglect SI and PI, you may encounter problems such as signal distortion, crosstalk, jitter, ringing, reflections, ground bounce, voltage drop, noise coupling, or electromagnetic interference. These problems can cause errors, glitches, data loss, or even damage to your hardware. Therefore, it is essential to consider SI and PI in every stage of your hardware development process, from design to testing to deployment.

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Mohammed Abid Ali

CEO and Co-founder at Ardencraft Technology
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Why do SI and PI mistakes keep showing up in hardware development even with all the tools, specs, and checklists available? The reality is that even experienced teams often overlook signal integrity (SI) and power integrity (PI) challenges until they become visible problems. And it is not because the tools are not good enough. It is because SI and PI are still treated as late-stage checks rather than design priorities.

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3 How to avoid SI mistakes?

Hardware developers commonly make mistakes in SI, such as using incorrect or mismatched impedance values for the signal paths, which can lead to signal quality degradation. To prevent this, impedance matching techniques such as termination, stub removal, or differential signaling should be used. Additionally, ignoring the effects of parasitic capacitance and inductance on the signal paths can create unwanted resonances, delays, or attenuation that affect the signal timing and shape. To avoid this, the length and width of the signal traces should be minimized, appropriate routing and layering strategies should be implemented, and sharp bends or corners should be avoided. Furthermore, crosstalk or noise coupling on the signal paths should be taken into account as these can interfere with signals due to electromagnetic coupling or shared return paths. To prevent this from occurring, the signal traces should be separated by enough distance or shielding, ground planes or vias should be used to provide low impedance return paths, and noise sources should be filtered or isolated.

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Mohammed Abid Ali

CEO and Co-founder at Ardencraft Technology
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Here is what we often see. A common SI misconception is thinking that if a trace looks short on the PCB, it cannot be a transmission line. The truth is, even a few centimeters can introduce reflections, crosstalk, and timing errors at high frequencies. A common PI misconception is relying entirely on decoupling capacitors. They do help, but without a low-impedance power delivery network and proper placement, the problem remains hidden until it affects system performance.

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4 How to avoid PI mistakes?

Hardware developers can make several mistakes when it comes to PI, such as using inadequate or inappropriate power supply components or circuits, neglecting the effects of parasitic resistance and inductance on the power paths, and not considering the impact of load variations or switching noise on the power paths. To avoid these issues, developers should employ proper power supply design techniques, minimize the length and width of power traces, monitor and control the load current and voltage, use appropriate routing and layering strategies, employ load sharing or sequencing techniques, and limit or suppress the switching noise.

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Mohammed Abid Ali

CEO and Co-founder at Ardencraft Technology
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So how can these traps be avoided? The first step is to think about SI and PI from the very beginning of the design. It should be part of the architecture, not just an analysis at the end. Next, teams need to collaborate more closely. Electrical, mechanical, and layout engineers must be aligned on what good integrity looks like. And finally, the choice of stackup and via strategy should be intentional. These decisions directly affect impedance, noise, and stability.

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5 How to overcome SI and PI misconceptions?

Hardware developers often have misconceptions about SI and PI, such as that they are independent or unrelated. However, in reality, SI and PI are interdependent and influence one another. Additionally, SI and PI are relevant for any design that involves signals and power, regardless of the speed or frequency. Furthermore, SI and PI are dynamic and probabilistic, as they may vary depending on environmental conditions or component aging. Therefore, it is important to consider both SI and PI as a holistic system, optimize them together, check them with appropriate tools and methods, and validate their performance under different scenarios and margins.

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Mohammed Abid Ali

CEO and Co-founder at Ardencraft Technology
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At Ardencraft, we make SI and PI part of our development culture from the first trace to the final test. We are also starting to see AI surface subtle integrity issues that were hard to catch with traditional methods. Now we would love to hear from you. What SI or PI mistake have you encountered that taught you something valuable? Share your experience. Let us build a practical conversation that helps the community design better.

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6 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?

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Martin Brochet

Southern Europe Senior Account Executive
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Delivering Accurate SI/PI Analysis with a Comprehensive Solution for Meeting Compressed Schedules of High-Speed Electronic Products. The increased complexity of electronic product design and the growing demand for denser, smaller products can be challenging and delay time to market. To address these requirements, design engineers need advanced, power-aware signal and power integrity (SI/PI) technologies that are integral to your design platform and can be used seamlessly throughout the design process. Sigrity Signal and Power Integrity is a Powerful signal integrity and PDN analysis and interconnect modeling for PCB and IC package designs

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What are the most common SI and PI mistakes and misconceptions in hardware development?

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1 What is SI and PI?

2 Why do SI and PI matter?

3 How to avoid SI mistakes?

4 How to avoid PI mistakes?

5 How to overcome SI and PI misconceptions?

6 Here’s what else to consider

Hardware Development

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