Signal integrity basics by anritsu field application engineers table of contents 1. Find and fix weaknesses in ddr234 and lpddr234 designs with just a few clicks using the ddrx wizard. As the signals frequency content increases, these effects become more significant. Signal integrity basics intel data center solutions.
Emphasis is placed on real problems that the author has encountered in his professional career, integrating problemsolving strategies and real signalintegrity case studies throughout the presentation. Hyperlynx signal integrity delivers advanced tools for optimizing serdes design projects. This tutorial relates to the example project nbp28. Faster switching times cause higher transient currents within the outputs as the load capacitors discharge. Digital signals on transmission lines by gary breed editorial director s ignal integrity is one of the hot topics in digital circuit design. Not doing signal integrity analysis can be more expensive. Tu01 performing signal integrity analyses version v1. Signal integrity analysis tongtong yu zhiyuan shen. Over short distances and at low bit rates, a simple conductor can transmit. For example, board capacitance, which is nominally very low in the picofarad. Accurate signal integrity analysis results product demo. A fully uptodate introduction to signal integrity and physical designhow design and technology selection can make or break the performance of the power distribution networkexploration of key concepts, such as plane impedance, spreading inductance, decoupling capacitors, and capacitor loop inductancepractical techniques for analyzing. Signal integrity engineering is at all levels of electronics packaging, from internal connections of an ic through the package, the printed circuit board pcb, the backplane, and intersystem connections. In my latest article in the may 2017 issue of ieee electromagnetic compatibility magazine, my former student, karthik radhakrishna, and i describe a simple process using an open source tool to concatenate sparameter elements sparameters are often called a behavioral model for interconnects.
Dale williams, mph, phd professor of medicine and biostatistics. Hyperlynx signal integrity analysis student workbook. These can include simple parallel termination on stratix gx devices as shown in figure 2, and can range to more complex resistor capacitor rc termination, in which an rc network provides a lowpass filter to remove low frequency effects, but passes the highfrequency signal. What is the objective of signal integrity analysis. Any time an electrical signal is transmitted, signal integrity is a concern. Topics that will be addressed include lumped discontinuities. Signal integrity jun fan, associate editor w elcome to the signal integrity column. Tektronix delivers the bandwidth and timesaving features you need to properly address highspeed signal deviations, quickly locate and trace faults back to their source.
Laird signal integrity products distributor digikey. Historically, pulsed signals were measured with an oscilloscope or digital signal analyzer. Share this post share on twitter share on linkedin share on facebook. With modern digital electronic systems pushing beyond the 1ghz barrier, packaging and board designers must now balance signal integrity and electrical performance with these other concerns. And also, when it gets there, is it in good condition. A number of different termination methods are used to overcome this problem, depending on the application. You might be forced to reduce the clock rate just to get the system to work, or be forced into a complete board redesign to correct signal integrity issues. Semiconductor engineering sat down to discuss signal integrity with rob aitken, research fellow at arm. Signal and power integrity tutorials in ads youtube. Over short distances and at low bit rates, a simple conductor can transmit this with sufficient fidelity. Mentor graphics reserves the right to make changes in specifications and other information contained in this publication without prior notice, and the.
A digital designers guide to verifying signal integrity primer. As the speed of the data signal increases a number of reasons. Highspeed board designers have come to rely upon the venerable ipcd317, design guide for electronic packaging utilizing highspeed. Established in 1876, laird signal integrity products has corporate offices in chattanooga, tennessee, usa with two manufacturing. Does the signal reach its destination when it is supposed to. Signal integrity 101 a brief overview of signal integrity and where it fits in the digital design process. Transmission line effect interconnection effect different from traditional circuit analysis. Introduction this module describes the purpose of the course and the general approach followed for addressing this purpose. To begin this series on fundamentals of signal integrity, lets start at the very beginning. New to signal integrity analysis, or just need to brush up on the fundamentals. Signal integrity basics all signals transmitted through a medium such as a pcb trace or coaxial cable are affected by various physical phenomena. In this issue, you will find a very interesting paper on power integrity. Students are challenged to think about managing complex design projects and implementing successful engineering and manufacturing processes. Basic principles of signal integrity altera corporation simultaneous switching output sso effects on signal integrity as digital circuitry speed increases, outputswitching times decrease.
Fundamentals of signal integrity analysis mentor graphics. This document is for information and instruction purposes. Each component will be assigned a status as described in the following table. In modern highspeed digital designs, power distribution networks pdns using power and ground planes are commonly used where decoupling capacitors are necessary to provide charge for. However, digital signals are fundamentally analog in nature, and all signals are subject to effects such as noise, distortion, and loss. Ensure the reliable operation of a digital design by predicting, measuring and modifying the behavior. Introduction high speed pcb design referes to the techniques that must be followed in order for a circuit to function properly when the edge rate of the signal is high. The paper begins by identifying and analyzing critical nets in the design that may need signal integrity analysis.
Issues, tools and methodologies pdf this series of articles explores tools and methods you can use to combat signal and power integrity distortions throughout product development. The presentation is intended for an audience that has little or no formal training in electromagnetic theory and microwave engineering. Ringing and overshoot large overshoot damage device crossing logic threshold. Tutorial checking signal integrity on an fpga design. Come back to the signal integrity academy and log in to then access all the lessons. In digital electronics, a stream of binary values is represented by a voltage or current waveform. Power supply decoupling becomes far less effective, as ground planes and power. Review of signal integrity concepts at frequencies in the gigahertz range, a host of variables can affect signal integrity. Signal integrity problems increase at higher frequencies.
Drawing upon the cuttingedge research of professor paul hurays team of industrial engineers and graduate students, it develops the physical. The course alternates between teaching the essential theory and how to use simulations as part of daytoday design work in an efficient way using industry standard ibis simulators etc. The task of isolating and eliminating signal integrity problems anywhere in a systems is challenging. Next, it discusses transmission lines and the problems that arise from the highfrequency noise generated by rapid edgerate signals. They describe everything there is to know about the electrical properties of an interconnect. Preface printed circuitboard and icpackage design used to be a field that involved expertise in layout, cad, logic design, heat transfer, mechanical engineering, and reliability analysis. With the advent of todays gigabit data rates, bit error rate testing bert has become the measurement of choice. Impedance discontinuities along the signal path create reflections, which degrade signal edges. Hyperlynx business and technical value technology overview. Pcad signal integrity utilizes the pcad pcb, dbx api interface for interactive communications. Pcad signal integrity users guide 3 supporting the ibis 3 industry standard subset for io buffer modeling. Prjpcb, which can be found in the \examples\signal integrity\nbp28 folder of the altium designer examples. A digital designers guide to verifying signal integrity.
Signal integrity tutorial this tutorial is intended for printed circuit board designers who wish to get an insight into the design of high speed digital pcbs. Signal integrity is the ability of an electrical signal to carry information reliably and to resist the effects of highfrequency electromagnetic interference from nearby signals. Integrated macromodeleditor allows easy and fast definition of own models using databook or measurement values. Signal integrity with handson simulation is a 3day training course in practical signal integrity for board level design and layout engineers. It covers setting up design parameters like design rules and signal integrity models, starting up signal integrity from the schematic and pcb editors, configuring the tests to be used in the net screening analysis, running further analysis on selected nets, terminating the signal line, setting preferences and working with the. Having good signal integrity usually means controlling unwanted noise on logic sig. Signal integrity for pcb designers introduction chapter 1 hiring a signal integrity engineer is expensive. Signal integrity pcb considerations during the circuit. Some of the main issues of concern for signal integrity are ringing, crosstalk. The goal of signal integrity analysis is to ensure reliable highspeed data transmission. The foundations of signal integrity is the first of its kind. This daughterboard includes a xilinx spartan 3, a sharp lh79520 incorporating an arm 7 processor, sram and flash memory. Formerly known as steward is the leading producer of ferrite and related materials used in the electronics, copier, telecommunications, military and automotive industries.
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