Signal Integrity Basics
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Modeling System Signal Integrity Uncertainty Considerations
WHITE PAPER Intel® FPGA Modeling System Signal Integrity Uncertainty Considerations Authors Abstract Ravindra Gali This white paper describes signal integrity (SI) mechanisms that cause system-level High-Speed I/O Applications timing uncertainty and how these mechanisms are modeled in the Intel® Quartus® Engineering, Intel® Corporation Prime software Timing Analyzer to achieve timing closure for external memory interface designs. Zhi Wong By using the Intel Quartus Prime software to achieve timing closure for external High-Speed I/O Applications memory interfaces, a designer does not need to allocate a separate SI timing Engineering, Intel Corporation budget to account for simultaneous switching output (SSO), simultaneous Navid Azizi switching input (SSI), intersymbol interference (ISI), and board-level crosstalk for Software Engineeringr flip-chip device families such as Stratix® IV and Arria® II FPGAs for typical user Intel Corporation implementation of external memory interfaces following good board design practices. John Oh High-Speed I/O Applications Introduction Engineering, Intel Corporation The widening performance gap between FPGAs, microprocessors, and memory Arun VR devices, along with the growth of memory-intensive applications, are driving the Memory I/O Applications Engineering, need for faster memory technologies. This push to higher bandwidths has been Intel Corporation accompanied by an increase in the signal count and the signaling rates of FPGAs and memory devices. In order to attain faster bandwidths, device makers continue to reduce the supply voltage. Initially, industry-standard DIMMs operated at 5 V. However, due to improvements in DRAM storage density, the operating voltage was decreased to 3.3 V (SDR), then to 2.5V (DDR), 1.8 V (DDR2), 1.5 V (DDR3), and 1.35 V (DDR3) to allow the memory to run faster and consume less power. -
Measuring OTDR Reflectance and ORL
TECHNICAL NOTE Measuring OTDR Reflectance and ORL Overview Optical Return Loss (ORL) is the ratio between the light launched into a device and the light reflected by a defined length or region. ORL can be measured using two measurement techniques: optical continuous wave reflectometry (OCWR) or optical time domain reflectometry (OTDR). Both techniques are described in IEC 61300-3-6. This paper will briefly describe the OCWR method, but the emphasis will be on the OTDR method. While the OCWR method is more accurate, the time-domain method has become the more popular tool primarily due to its ease-of-use and ability to characterize total fiber spans results as well as individual event location, loss and reflectance. OTDRs can measure reflectance and total ORL for a fiber span. Return Loss (RL) of individual events, i.e. the reflection above the fiber backscatter level, relative to the source pulse scatter, is called reflectance. Return Loss of a fiber span is referred to as ORL. Both reflectance and ORL are in units of dB but reflectance is always a negative value while ORL is a positive value. Larger reflections indicate bad reflectance or -14dB, or 4% Fresnel reflection indicating poor connection. ORL and reflectance measurement results can be impacted by contaminated connectors so proper cleaning and inspection is critical prior to any measurement to ensure accurate and repeatable results. RL on a mated optical connector is ORL but when measured using OTDR, it is called reflectance. The ORL of a connector can change over time with repeated mating due to small changes to the surface. -
Shahabi-Adib-Masc-ECE-August
A New Line Code for a Digital Communication System by Adib Shahabi Submitted in partial fulfilment of the requirements for the degree of Master of Applied Science at Dalhousie University Halifax, Nova Scotia August 2019 © Copyright by Adib Shahabi, 2019 To my wife Shahideh ii TABLE OF CONTENTS LIST OF TABLES ............................................................................................................ v LIST OF FIGURES .......................................................................................................... vi ABSTRACT ....................................................................................................................viii LIST OF ABBREVIATIONS USED ............................................................................... ix ACKNOWLEDGEMENTS ............................................................................................... x CHAPTER 1 INTRODUCTION ....................................................................................... 1 1.1 BACKGROUND ........................................................................................... 1 1.2 THESIS SYNOPSIS ...................................................................................... 4 1.3 ORGANIZATION OF THE THESIS ............................................................ 5 CHAPTER 2 MODELLING THE LINE CHANNEL ....................................................... 7 2.1 CABLE MODELLING .................................................................................. 7 2.2 TRANSFORMER COUPLING .................................................................. -
The Printed Circuit Designer's Guide To... Signal Integrity by Example
PEER REVIEWERS This book has been reviewed for technical accuracy by the following experts from the PCB industry. Happy Holden Consulting Technical Editor, I-Connect007 Happy Holden is the retired director of electronics and innovations for Gentex Corporation. Happy is the former chief technical officer for the world’s largest PCB fabricator, Hon Hai Precision Industries (Foxconn). Prior to Foxconn, Holden was the senior PCB technologist for Mentor Graphics and advanced technology manager at Nan Ya/ Westwood Associates and Merix. Happy previously worked at Hewlett-Packard for over 28 years as director of PCB R&D and manufacturing engineering manager. He has been involved in advanced PCB technologies for over 47 years. Eric Bogatin Eric Bogatin is currently the dean of the Teledyne LeCroy Signal Integrity Academy. Additionally, he is an adjunct professor at the University of Colorado- Boulder in the ECEE department, where he teaches a graduate class in signal integrity and is also the editor of Signal Integrity Journal. Bogatin received his BS in physics from MIT, and MS and PhD in physics from the University of Arizona in Tucson. Eric has held senior engineering and management positions at Bell Labs, Raychem, Sun Microsystems, Ansoft and Interconnect Devices. Bogatin has written six technical books in the field, and presented classes and lectures on signal integrity worldwide. MEET THE AUTHOR Fadi Deek Signal/Power Integrity Specialist Corporate Application Engineer In 2005, Fadi received his B.S. degree in computer and communications from the American University of Science and Technology (AUST) in Beirut, Lebanon. That same year, he joined Fidus Systems as a design engineer. -
A Guide to Making RF Measurements for Signal Integrity Applications
White Paper A Guide to Making RF Measurements for Signal Integrity Applications Introduction Designing a system for Signal Integrity requires a great deal of knowledge and tremendous effort from all disciplines involved. Higher data rates and more complex modulation schemes are requiring digital engineers to take into account the analog and RF performance of the channels to a much greater degree than in the past. Moreover, increasing performance demands are requiring digital engineers move from oscilloscopes and TDRs to vector network analyzers (VNAs), with which they may be less familiar. Correspondingly, RF measurement groups within companies are being called on by their digital colleagues to help them with making VNA measurements. This paper is intended to review signal integrity-based VNA measurements for digital engineers and correlate VNA measurements to key signal integrity parameters for RF engineers. Contents The Driving Need for RF Measurements ...........................................................................................................3 Understanding Signal Integrity Terms and Measurements ...........................................................................4 Eye Diagrams .................................................................................................................................................4 Dispersion .......................................................................................................................................................4 High Frequency Loss /Attenuation -
Design and Performance Evaluation of QPSK Modulation And
International Conference on Applied Science and Engineering Innovation (ASEI 2015) Design and Performance Evaluation of QPSK Modulation and Demodulation in SS mode Based on Systemview Sheng LIANGa, Gaofeng PANb, Youxing WU, Yong XIEc China Satellite Maritime Tracking and Control Department, Jiangyin, Jiangsu, 214431,China a [email protected], b [email protected], c [email protected] Keywords: SS; QPSK; Eye Diagram. Abstract. Because the modulation and demodulation method in SS (Spread Spectrum) mode is different with sub-carrier TT&C system, so it is necessary to realize its performance evaluation based on software simulation. This paper makes use of Systemview to simulate the single target measurement in SS system and evaluate its anti-noise performance by eye diagram and BER. Results show the simulation model designed in this paper is feasible and Systemview can visualize abstract communication simulation. Introduction The present SS TT&C system has two kinds, which are coherent and non-coherent SS modes. In coherent mode, telecommand message is embedded in branch I of QPSK modulation after encoded with short PN code (period 210-1), distance measure message is embedded in branch Q after encoded with long PN code (period (210-1)×256) and the two branch signals with different powers compose UQPSK signal. In non-coherent mode, two branch messages encoded with short PN code are BPSK modulated respectively, which will be transmitted to the satellite after up-conversion and power amplification. This paper sets conditions to unitize the two modes and designs the modulation & demodulation simulation model based on Systemview to evaluate performance of SS mode. -
Understanding Optical Time Domain Reflectometers (OTDR) Specifications
WHITE PAPER Understanding Optical Time Domain Reflectometers (OTDR) Specifications December 2020 | Rev. A00 P/N: D08-00-087 VeEX Inc. 2827 Lakeview Court, Fremont, CA 94538 USA Tel: +1.510.651.0500 Fax: +1.510.651.0505 www.veexinc.com Understanding Optical Time Domain Reflectometers (OTDR) Notice: The information contained in this document is subject to change without notice. VeEX Inc. makes no warranty of any kind with regard to this material, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose. VeEX shall not be liable for errors contained herein or for incidental or consequential damages in connection with the furnishing, performance, or use of this material. The features or functions described in this document may or may not be available in your test equipment or may look slightly different. Make sure it is updated to the latest software packages available and that is has any related licenses that may be required. For assistance or questions related to this document and procedures, or to get a test set serviced by VeEX or an authorized service facility, please contact: VeEX Inc. Phone: +1 510 651 0500 E-mail: [email protected] Web: www.veexinc.com ©Copyright VeEX Inc. All rights reserved. VeEX, VePAL are registered trademarks of VeEX Inc. and/or its affiliates in the USA and certain other countries. All other trademarks or registered trademarks are the property of their respective companies. No part of this document may be reproduced or transmitted electronically or otherwise without written permission from VeEX Inc. VeEX Inc. -
Baluns & Common Mode Chokes
Baluns & Common Mode Chokes Bill Leonard N0CU 5 August 2017 Topics – Part 1 • A Radio Frequency Interference (RFI) Problem • Some Basic Terms & Theory • Baluns & Chokes • What is a Balun • Types of Baluns • Balun Applications • Design & Performance Issues • Voltage Balun • Current Balun • What is a Common Mode Choke • How a Balun/Choke works Topics – Part 2 • Tripole • Risk of Installing a Balun • How to Reduce Common Mode currents • How to Build Current Baluns & Chokes • Transmission Line Transformers (TLT) • Examples of Current Chokes • Ferrite & Powdered Iron (Iron Powder) Suppliers Part 1 RFI Problem • Problem: • Audio started coming thru speakers of audio amp: • When transmitting > 50W SSB • 20M & 40m (I didn’t check any other bands) • No other electronics affected • Never had this problem before • Problem would come and go for no apparent reason RFI Problem – cont’d • Observations • Intermittent: problem was freq dependent • RF Power level dependent • Rotating the 20 M beam appeared to have no effect • No RFI with dummy load • AC line filter had no effect • Common Mode Choke on transmission line to house had no effect • Caps (180 pF) on speaker terminals on audio amp made problem worse • Caution: don’t use large caps (ie., 0.01 uF) with solid state amps => damage • Disconnecting 4 of 5 speakers from the audio amp eliminated problem • The two speakers with the longest cables were picking up RF • Both of these speakers needed to be connected to the amp to have the problem • Length of cable to each speaker ~30 ft (~1/4 wavelength on -
Design of Contactless Capacitive Power Transfer Systems for Battery Charging Applications
Design of Contactless Capacitive Power Transfer Systems for Battery Charging Applications By DEEPAK ROZARIO A Thesis Submitted in Partial Fulfilment of the Requirements for the Degree of Master of Applied Science in The Faculty of Engineering and Applied Sciences Program UNIVERSITY OF ONTARIO INSTITUTE OF TECHNOLOGY APRIL, 2016 ©DEEPAK ROZARIO, 2016 ABSTRACT Several forms for wireless power transfer exists - Microwave, Laser, Sound, Inductive, Capacitive etc. Among these, the Inductive Power Transfer Systems (IPT) are the most extensively used form of wireless power transfer. Due to the utilization of magnetics the inductive power transfer system suffers from Electromagnetic Interference (EMI) issues. Due to the utilization of magnetic field to transfer power, the system is not preferred in an environment with metals and cannot transfer power through metal barriers. Capacitive Power Transfer System (CPT) is an emerging field in the area of wireless power transfer. The antennae of the CPT system, constitute two metal plates which are separated by a dielectric (air). When energised, the metal plates along with the dielectric resemble a loosely coupled capacitor, hence the term capacitive power transfer. The capacitive system utilizes electric field to transfer power and therefore eliminating electromagnetic interference issues. The system has low standing power losses, good anti-interference ability. The advantages, make the CPT system a dynamic alternative to the traditional wireless inductive system. As the area is still in its infancy, the first part of this thesis is dedicated to an extensive study on the literature available on the CPT systems and the basic operation of the system. From, the study it was evident that CPT systems have efficiencies ranging between 60% to 80%. -
Reference Guide to Fiber Optic Testing Product Speci Cations and Descriptions in This Document Subject to Change Without Notice
Reference Guide to Fiber Optic Testing Optic Fiber Guide to Reference Reference Guide to Fiber Optic Testing Product specications and descriptions in this document subject to change without notice. © 2010 JDS Uniphase Corporation SECOND EDITION Volume 1 SECOND EDITION SECOND 30149054.002.0710.FIBERGUIDE1.BK.FOP.TM.AE Test & Measurement Regional Sales Volume 1 Volume North America Latin America Asia Pacic EMEA www.jdsu.com Toll Free: 1 866 228 3762 Tel: +1 954 688 5660 Tel: +852 2892 0990 Tel.: +49 7121 86 2222 Tel: +1 301 353 1560 x 2850 Fax: +1 954 345 4668 Fax: +852 2892 0770 Fax: +49 7121 86 1222 Fax: +1 301 353 9216 Reference Guide to Fiber Optic Testing SECOND EDITION Volume 1 By J. Laferrière G. Lietaert R. Taws S. Wolszczak Contact the authors JDSU 34 rue Necker 42000 Saint-Etienne France Tel. +33 (0) 4 77 47 89 00 Fax +33 (0) 4 77 47 89 70 Stay Informed To be alerted by email to availability of newly published chapters to this guide, go to www.jdsu.com/fiberguide2 Copyright© 2011, JDS Uniphase Corporation All rights reserved. The information contained in this document is the property of JDSU. No part of this book may be reproduced or utilized in any form or means, electronic or mechanical, including photocopying, recording, or by any information storage and retrieval system, without permission in writing from the publisher. JDSU shall not be liable for errors contained herein. All terms mentioned in this book that are known to be trademarks or service marks have been appropriately indicated. -
Operational Amplifier “Op Amp”
Buffering • You saw that the parallel resistor lowers the voltage • A voltage measurement device with a non-infinite resistance does the same; we would therefore like a way to connect a voltmeter to the touchscreen without loading the system and lowering the voltage • This is easily done using a buffer. A buffer has a high input resistance, but can source the current needed by the load. Energy needed by load from another supply as needed. Input voltage High input reproduced at resistance output • In effect, a buffer (nearly) reproduces the input voltage, but doesn’t load the input • Note that a buffer cannot produce energy, so it draws the energy the load requests from some other power supply 49 Amplifier Integrated Circuits • In an ideal world, an amplifier IC takes an input signal (for example, Vin), and multiplies it by a fixed amount to produce an output signal. Example: Vout = AVVin where AV is the multiplier, called a voltage gain • Of course, the energy for this multiplication has to come from somewhere. Therefore, an amplifier IC has power supply connections as well. 50 Operational Amplifier “Op Amp” • Two input terminals, positive (non- inverting) and negative (inverting) • One output • Power supply V+ , and Op Amp with power supply not shown (which is how we usually display op amp circuits) 51 Equivalent Circuit and Specifications • In other words, a really good buffer, since Ri . All the needed power for the output is drawn from the supply 52 Gain of an Op Amp • Key characteristic of op amp: high voltage gain • Output, A, is -
Analysis and Modeling of Capacitive Coupling Along Metal Interconnect Lines by Andrew K
Analysis and Modeling of Capacitive Coupling Along Metal Interconnect Lines by Andrew K. Percey Submitted to the Department of Electrical Engineering and Computer Science in partial fulfillment of the requirements for the degrees of Bachelor of Science in Electrical Science and Engineering and Master of Engineering in Electrical Engineering and Computer Science at the MASSACHUSETTS INSTITUTE OF TECHNOLOGY June 1996 @ Andrew K. Percey, MCMXCVI. All rights reserved. The author hereby grants to MIT permission to reproduce and distribute publicly paper and electronic copies of this thesis document in whole or in part, and to grant others the right to do so. MASSACH'USETTS NSTi'U L' OF TECHNOLOGY JUN 1 1996 Author............ LIBRARIES Department of Electrical Engineering andCo mputer Science Eng. May 28, 1996 Certified by .......... ........ ...... Jacob White Professor of Electrical Engineering ",sis Supervisor A ccepted ',, ....I........... .. ............... ............. F. R. Morgenthaler Chairman, Departme Committee on Graduate Theses Analysis and Modeling of Capacitive Coupling Along Metal Interconnect Lines by Andrew K. Percey Submitted to the Department of Electrical Engineering and Computer Science on May 28, 1996, in partial fulfillment of the requirements for the degrees of Bachelor of Science in Electrical Science and Engineering and Master of Engineering in Electrical Engineering and Computer Science Abstract Electrical signals propagating along metal interconnect lines within contemporary microchips experience significant delay and noise due to capacitive coupling effects. Analysis and modeling of these effects was performed at the author's VI-A Internship company. Numerous CAD circuit simulations were performed to acquire a better understanding of these coupling effects. A program was created to assist circuit designers in analyzing these effects for their particular circuit topologies.