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PCB Transmission Lines
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PCB Transmission Lines

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Transmission Line and PCB Track Design Transmission Lines in PCB Track Design Digital designs fall broadly into two categories: low-speed and high-speed. The category “high speed” does not necessarily mean a high clock rate. Rather, it refers to the rise time of the signal during switching, which leads to propagating wave behavior on long PCB tracks. When a PCB track gets too long, it needs to be designed like a transmission line, not just a simple conductor with DC resistance. Understanding how to design transmission Read Article
UTP cable differential pairs without ground Differential Pairs Without a Ground Plane: Is it a Problem? Some designers tell you that differential pairs without ground are acceptable. So who’s correct? We’ll examine the pros and cons of a differential pair ground plane. Read Article
Why is There a Transmission Line Critical Length? Why is There a Transmission Line Critical Length? There is a little secret that most literature on PCB design will not tell you. Read & find out what you need to know about determining the transmission line critical length in your PCB interconnects. Read Article
Can You Use Series and Parallel Termination on the Same Net? Can You Use Series and Parallel Termination on the Same Net? Series and parallel termination are the most common resistive termination options for digital signaling. The reason is that resistance is a wideband quantity and does not start to be affected by parasitics until well into the GHz range. At the channel bandwidth associated with most digital signals, there are cases where an unterminated line actually needs termination, even if there is no impedance specification in the interface. As both options Read Article
Simulation Driven PCB Design Simulation Driven Design Can Solve Your PCB’s Signal Problems and More If you work in the electronics industry or in research, there’s a chance that simulations are a regular part of life. Simpler systems can be designed with intuition and simulated after designs are completed, but more advanced systems running at high frequencies or very high data rates need qualification before and after a PCB layout is complete. Simulation software has to take a more prominent role in PCB design for many advanced systems Read Article
Knee Frequency Derivation Where Does the Knee Frequency Formula Come From? The knee frequency has nothing to do with signal bandwidth, but it has everything to do with channel bandwidth. Read Article
PCB critical length Can We All Stop Quoting the Critical Length Rule? Let’s all agree to stop using the PCB critical length rule in high-speed PCB design. Read Article
Reflectionless Matching vs. Conjugate Matching Reflectionless Matching vs. Conjugate Matching: An Apparent Contradiction Are reflectionless matching and conjugate matching contradictory? When we look at the formulation for power waves and S-parameters, we see where these are different. Read Article
NVMe M.2 PCIe connector stubs A Brief Study of Stubs on a PCIe Connector Stubs are an important topic in high-speed PCB design, and there is a longstanding guideline that stubs should always be removed from all vias on high-speed digital interconnects. While stubs are bad for high-speed lines, they do not always need to be removed. What is more important is to predict the loss profile and frequencies, and to floorplan appropriately to try and prevent such losses. In this article, I’ll look at some simulation results Read Article
Stripline impedance calculator Stripline Impedance Calculator Learn more about using and interpreting results from a microstrip impedance calculator. Read Article
Microstrip impedance calculator Microstrip Impedance Calculator Learn more about using and interpreting results from a microstrip impedance calculator. Read Article
Differential stripline impedance calculator Differential Stripline Impedance Calculator Try our differential stripline impedance calculator, built based on Wadell’s equations. Read Article
Differential Microstrip Impedance Calculator Differential Microstrip Impedance Calculator Learn more about using and interpreting results from a differential microstrip impedance calculator. Read Article
differential pair impedance calculator Differential Pair Impedance: Using a Calculator to Design Your PCB Do you know what to look for in your differential pair impedance calculator? We've compiled the important information you need to know in this short guide. Read Article
Reduce copper losses Recover Conductor Losses By Clearing Your PCB Ground Layer Need to recover some conductor losses? Here’s how clearing out your ground plane near an I/O or connector can help. Read Article
PCB routing What is PCB Routing? Learn about PCB routing techniques and how to design traces to proper routing in any device. You can access the best PCB routing features in Altium Designer. Read Article
Wideband signal integrity Wideband Signal Processing and Analysis in Ultra-high Speed PCB Design Wideband signal analysis may seem like black magic, but it does more than create pretty graphs. Read our introduction to wideband signal analysis to learn more. Read Article