Refreshments and a buffet dinner will be hosted by the SCV EMC Chapter, after which the new officers will be introduced and each will provide a short presentation on their plans for 1997-98. It would be greatly appreciated if you could call either Geoff Day at 408-756-9919 or Mike Royer at 415-780-4218 if you (and your spouse or significant other) plan on attending.
The chapter also invites prospective speakers to attend this session and submit presentation outlines for consideration. Suggested topics include: measurements (techniques, technology, problems, corrections, calibration); test facilities (shielded rooms, open field test sites, screen rooms, anechoic and semi-anechoic chambers); EM noise sources and studies; design for reduced noise; electrostatic discharge; antennas and propagation; EMC standards and regulations; and computer aided analysis and design. Anyone interested in presenting an outline of these or other appropriate topics should contact Geoff Day at (408) 756-9919.
The method was successfully applied to develop a strategy for improving the performance of the ten meter absorber lines chamber at the Hewlett Packard Hardware Test Center in Cupertino. An overview of the analysis of the site and a discussion of the retrofit will be presented.
Ron Pratt joined the Hewlett Packard Company in 1967 and spent most of his career developing microwave instruments for signal generation, network analysis as well as power and noise figure measurements. EMC was always an important part of that work and for the last several years he has focused on those problems.
Ron received his BSEE from New Jersey Institute of Technology in 1967. For almost 20 years Ron taught a very successful microwave measurements course at Foothill College. He is a contributing author to the Reference Data Engineers: Radio, Electronics, Computer, and Communications and the Electronic Instrument Handbook. Ron is a member of IEEE EMC Society and is a NARTE certified EMC Engineer.
In this presentation, the EMI characteristics of a densely packed high speed computer motherboard involving clock and bus speeds up to 200MHz with signal rise times in the order of 400 pico-seconds is analyzed extensively. Actual measured comparisons of radiated emissions and power bus transfer impedance are presented for the original motherboard and for the case of the motherboard with additional power and ground planes included. A discussion of general decoupling methodology for multi-layer boards will also be presented.
Biography: Neilus O'Sullivan received his B.Eng. degree from the University of Limerick in Ireland in 1989 and his Ph.D degree in electromagnetics from the same university in 1995. He has worked for Analog Devices B.V. as Test Characterisation Engineer and in 1989 joined automotive electronics manufacturer, Kostal Ireland as Research and Design engineer. From 1991 to 1995 he worked as consultant engineer to the broadcast industry in Ireland. At present he is employed by Sun Microsystems as EMC engineer at their Menlo Park facility. He has published a number of papers and presentations on various aspects of EMI, but his main area of interest is that of EMI control at printed circuit board level.
In the first presentation, the effects of radiated fields inducing unwanted common mode and differential mode currents onto signal cables are evaluated. Digital and analog control systems are exposed to the external electromagnetic noise produced by electrostatic discharge, EM fields from transmitters, and other sources. As a result the systems can start malfunctioning and the susceptibility problems arise. One of the main mechanisms of coupling of these external fields to the control systems is through the cables and wiring that act as receiving antennas. In this presentation the modeling results of two-wire lines excited by a uniform plane EM wave are analyzed using three different models. A lumped parameter model which is valid for lower frequencies and yields a simple analytical solution that is suitable for estimation purposes. For higher frequencies a transmission line model and an antenna model are used to accurately represent resonant behavior. This topic is being presented by Mary Wilson and Michael Mack.
In the second presentation, the effects of power supply switching noise on power distribution traces coupling onto adjacent signal lines are evaluated. Many state of the art microprocessors and ASIC integrated circuits are now powered by voltages that are less than the standard 5 VDC. With this reduced operating voltage, the susceptibility of the signal lines to noise increases. At the same time, these new operating voltages require on-board DC to DC converters that generate a substantial amount of switching noise. This switching noise can couple onto the signal lines, causing the system to malfunction. The noise generated can also have substantial harmonic content that can excite resonant structures within a system, causing it to exceed EMC conducted and radiated emission limits. Normally, power is distributed via power and ground planes in printed circuit boards. But because many of the circuits connected to these low voltage microprocessors and ASCII still operate at a nominal 5 volts, adding an extra low voltage plane adds cost, so this is not always a viable solution. The lowest cost solution is to route the low voltage power for the micro-processors and ASICs through wide traces on the same layers that contain signals. This increases the coupling efficiency between the power traces and adjacent signal traces. In such cases, one can use traditional trace to trace crosstalk coupling models to analyze the problem. This presentation discusses several rules for circuit board design that minimizes this interference. This topic is being presented by Edwin Salgado.
Michael Mack is a senior student majoring in Electrical Engineering at San Francisco State University. Michael has worked for several years in the communication and professional audio field as an technician and sales engineer. He has also worked as an intern with an acoustical engineering firm to develop software programs used to calculate noise criteria curves for HVAC systems.
Mary Wilson is an SFSU senior student majoring in Electrical Engineering with special emphasis on communications. She is also a full time EMC engineer at Bay Networks, where her emphasis is MOM and SPICE modelling of radiated emissions from cable arrays and microstrip geometries. She has also been an Electronic Technician for 8-years including 4-years in the United States Coast Guard working with RADAR systems.
Edwin Salgado is an SFSU senior student majoring in Electrical Engineering and Computer Science with a minor in Mathematics. Edwin has worked as an intern in the AT&T; Communications group writing code to simulate two antennas for wireless communication systems, and as an intern in the VSG EMC group at Silicon Graphics using HP VEE, NEC/INCASES Method of Moments, and Cray Research LC Finite Difference Time Domain modeling tools to do EMC computations as well as assist EMC engineers with performing EMC measurements. Edwin is currently working as an intern at Silicon Graphics in the Graphics Software Group as an Operating System Software Debugger.
BIOGRAPHY: Dr. Wheeler has a Ph.D in Electrical Engineering and Solid State Physics from Brigham Young University, Provo, UT. E.E. department with focus on Solid State Physics. He has over 26 years experience in industrial management, research, and hardware development, including: Bell Telephone Laboratories, Holmdel, NJ, Hewlett Packard Research Labs, Palo Alto, Ca. Presently, he is a management consultant for Hewlett Packard and evaluated multi-divisional VLSI packaging program for future computer products and recommended cost saving alternatives. Currently, he is acting as a technical advisor to a multi-divisional council responsible for coordinating flip chip development procedure across company boundaries and acting as a technical advisor to the Network Division to design CMOS driver/receiver circuits capable of operating greater than 1000 MHz. While at Fujitsu Computer Packaging Technologies, Inc., he managed the R&D; activity and played a key role in inventing a new type of interconnect between VLSI chips and PC boards. The new interconnect will allow computer CPUs to operate at clock frequencies above 1000 MHz. He was responsible for the technological design of high speed supercomputers, mainframes and workstations, bipolar and CMOS process and equipment design, and high speed networking: physical layer and OS interface. Dr. Wheeler has authored 16 patents and IEEE Proceedings paper.
BIOGRAPHY: Andy Griffin graduated from college in Nottingham, England in 1985, since that time has worked within the EMC industry. He has worked at Assessment Services, KTL , AWRE Aldermaston, IBM, CISCO Systems Inc [currently EMC Laboratory Manager] and as an independent consultant. In addition he is managing director of EMiSoft ltd, who generate EMC test software, provide EMC consultancy services and are co-authors of the EMC Compliance Manual [with ICC - Telecomm Approval Consultants] providing an in-depth analysis of worldwide EMC requirements for ITE and TTE. He is also a qualified Test Laboratory assessor covering the requirements of ISO 9001, EN45001. He is currently a member of the following EMC committees -ETSI EE4, GEL 210, GEL 210/7 and GEL 210/10 where he provides input into all CISPR/IEC
This presentation develops a simple but effective method of obtaining the Fourier Series of complex waveforms, and then analyzes several common problems normally encountered in the EMC field. Topics that will be covered include:
o Conceptual development of the Fourier Series from a piecewise linear
periodic waveform.
o An analysis of rectangular pulses that shows how decreasing the pulses
width often results in increasing harmonic levels.
o An analysis of symmetrical trapezoidal waveforms that show how a 10
MHz clock can actually have lower harmonic levels than a 1 MHz clock.
o An analysis of non-symmetrical rise/fall time trapezoidal waveforms
that shows how much reduction in harmonic levels one can obtain if only the
rise (or fall) time were increased.
o An analysis of trapezoidal waveforms having overshoots and ringing
and how much overshoot and ringing can be tolerated.
o An analysis of digital differential drivers and how the common
perception that differential driven signals are "somehow" less prone to cause
emission problems are not always true.
BIOGRAPHY: Franz Gisin has a BS(EE) from the University of Idaho, and an MS(Applied Mathematics) from the University of Santa Clara. He ahs been active in the EMC community for over 20 years, and is currently EMC Manager at Silicon Graphics Inc. He is a senior member of the EMC Society, a member of the EMC Society Board of Directors, and the Steering Committee Chair of EMC '98.
The New Approach Directive for Medical Devices (MDD) has far-reaching consequences for manufacturers and distributors who wish to place a product onto the market of the European Union (EU). Structured differently that either of the EMC or Low Voltage Directives, the MDD is an all-inclusive directive consisting of the following component parts:
Biography: Mr. Smith began his academic training as an electrical engineer, with a BSEE degree from Pacific Southern University. He has over 25 years experience in medical device and information technology equipment development and certification. John is a Senior Certification Engineer for the NELLCOR PURITAN BENNETT Hospital Division, a registered Professional Engineer and certified EMC engineer. He has a command of the European Directives' for Medical Devices and Electromagnetic Compatibility especially with respect to hazards, risk analysis, test and mitigation for product safety and EMC compliance.
John maintains membership with the AAMI, IEEE and NARTE and participates in the product safety, EMC and biomedical engineering chapters. He has served upon US Technical Advisory Groups for medical device requirements, has presented numerous seminars and papers to peers, colleagues and professional symposia and has authored two publications.
Mr. Smith was the regional EMC manager for ToV Product Service in San Diego prior to NELLCOR and specialized in certification, testing and engineering support for equipment and device manufacturers desiring compliance to domestic and international standards.
Before joining ToV-PS, John was employed with Alcon Laboratories as a member of the technical staff. His responsibilities included mentoring, conceptual and formal design reviews, regulatory compliance and product certification of medical devices for the Surgical Division. He also served as a Program Manager for a series of low cost, portable ophthalmic instruments intended for Europe, Japan and markets of developing countries.
Since both approaches have advantages, most EMC laboratories use spectrum analyzers and EMI receivers to accomplish their measurement tasks. For more than 10 years, spectrum-analyzer-based EMI receivers, called scanning or swept receivers, have become commercially available. This type of receiver combines the advantages of spectrum analyzers and dedicated EMI receivers in a single instrument. However, there are still concerns within the EMC community about the measurement capability of scanning receivers, their compliance with the specifications called out in the various standards, in particular CISPR (International Special Committee on Radio Interference) Publication 16 Part 1, and their suitability for EMI compliance measurements in general. This presentation compares the hardware architecture of a scanning and a traditional receiver, reviews the most important EMI receiver specifications and explains some practical issues related to the stepped versus swept measurement approach, the receiver frequency and display resolution, RF overload detection, and the discrimination between narrowband and broadband signals.
Mr. Shaefer is the Technical Contributor (EMC) at Hewlett-Packard Company. He has an extensive conducted and radiated emissions measurement practice background, including open area test site qualification and antenna calibration, development of EMI measurement software, and development and teaching of EMC classes at universities. He is an active member of CISPR A (EMI measurement equipment and procedures), ANSI C63 Subcommittee, SAE, IEEE EMC Society, and VDE/Germany. Mr. Schaefer has authored numerous publications on microwave measurement topics in technical journals in Europe, 10 papers on EMI measurement topics, given at EMC symposiums in Europe and USA, and co-authored a book on microwave measurement technology in Germany.