This accessible, new reference work shows how and why RF energy is created within a printed circuit board and the manner in which propagation occurs. With lucid explanations, this book enables engineers to grasp both the fundamentals of EMC theory and signal integrity and the mitigation process needed to prevent an EMC event. Author Montrose also shows the relationship between time and frequency domains to help you meet mandatory compliance requirements placed on printed circuit boards.
Using realworld examples the book features:

Clear discussions, without complex mathematical analysis, of flux minimization concepts
Extensive analysis of capacitor usage for various applications
Detailed examination of components characteristics with various grounding methodologies, including implementation techniques
An indepth study of transmission line theory
A careful look at signal integrity, crosstalk, and termination

Book Info
Reference text shows how & why RF energy is created within a printed circuit board, & the manner in which propagation occurs. Text enables engineers to grasp both the fundamentals of EMC event while maintaining optimal functionality for low & high technology products. DLC: Printed circuits Design & construction.

See all Editorial Reviews

Product Details

Hardcover: 325 pages
Publisher: WileyIEEE Press; 1st edition (August 31, 1998)
Language: English
ISBN10: 078034703X
ISBN13: 9780780347038
Product Dimensions: 10 x 7.2 x 0.9 inches
Shipping Weight: 1.8 pounds (View shipping rates and policies)
Average Customer Review:
3 Reviews
5 star: (2)
4 star: (0)
3 star: (1)
2 star: (0)
1 star: (0)

See all 3 customer reviews...

(3 customer reviews)
Amazon.com Sales Rank: #209,322 in Books (See Bestsellers in Books)
Popular in these categories: (What's this?)

#9 in Books > Computers & Internet > Computer Science > Circuitry > Electromagnetics
#13 in Books > Professional & Technical > Engineering > Electrical & Electronics > Circuits > Design
#24 in Books > Professional & Technical > Engineering > Special Topics > Measurement

(Publishers and authors: Improve Your Sales)
Also Available in: Hardcover (Onl) | All Editions

Would you like to update product info or give feedback on images? (We'll ask you to sign in so we can get back to you)


Inside This Book

Citations: This book cites 16 books
Explore: Citations | Books on Related Topics | Concordance | Text Stats
Key Phrases SIPs: chassis plane, localized ground plane, ground stitch locations, ground stitch connection, stackup assignment (more)
Key Phrases CAPs: John Wiley, New York, Noise Reduction Techniques, International Symposium, Controlling Radiated Emissions (more)
Browse Sample Pages: Front Cover | Copyright | Table of Contents | Excerpt | Index | Back Cover | Surprise Me!
Search Inside This Book:

Inside This Book (learn more)
First Sentence:
This book seeks primarily to help engineers minimize harmful interference between components, circuits, and systems. Read the first page
Key Phrases Statistically Improbable Phrases (SIPs): (learn more)
chassis plane, localized ground plane, ground stitch locations, ground stitch connection, stackup assignment, mutual partial inductance, grounded heatsink, maximum capacitive load, alternate return path, propagational delay, edge rate signal, microstrip topology, stitch connections, ground plane structure, routed trace, flux cancellation, cycle skew, trace impedance, pinout configuration, parallel termination, bifurcated lines, embedded microstrip, multipoint grounding, dual stripline, faster edge rate
Key Phrases Capitalized Phrases (CAPs): (learn more)
John Wiley, New York, Noise Reduction Techniques, International Symposium, Controlling Radiated Emissions, Englewood Cliffs, Van Doren, Van Nostrand Reinhold, High Speed Digital Design, Prentice Hall, Circuit Board Layout, Clayton Paul, Controlling CommonImpedance Coupling, Electronics Systems, The Designers Guide, North America, Oren Hartal, Parallel Cseries
New!
Books on Related Topics | Concordance | Text Stats
Browse Sample Pages:
Front Cover | Copyright | Table of Contents | Excerpt | Index | Back Cover | Surprise Me!
Search Inside This Book:

Citations (learn more)
This book cites 16 books:

Introduction to Electromagnetic Compatibility (Wiley Series in Microwave and Optical Engineering) by Clayton R. Paul on 10 pages
Noise Reduction Techniques in Electronic Systems, 2nd Edition by Henry Ott on 9 pages
Electromagnetic Compatibility by Design by Oren Hartal on 6 pages
Coombs' Printed Circuits Handbook by Clyde F. Coombs on page 182, page 277, and Back Matter
Spectrum and Network Measurements by Robert A. Witte on page 213, and Below you will find a great choice of freeware, shareware and free test versions. Please note that the rights to these product trademarks belong to the manufacturer. Beta layout Ltd. does not accept any legal liability that may occur due to the installation and use of these software products.

FREE: EDASoftware for PCBPOOL? customers

In cooperation with
Ing.Büro FRIEDRICH:

Download here your free
TARGET 3001!
PCBPOOL?Edition (6.8MB)
(for Win9X/Win2000/XP)

Current version:
10.2.1.159 (21.January 2003)
Future free updates are available:
www.pcbsino.com.....ibfriedrich.com/pcbpool.htm
PCBLayout
Simulation
Schematics
Autoplacer
Autorouter
EMVAnalysis
NO Demoversion
NO PinLimits
NO SizeLimits
Output only for PCBPOOL?


Screenshot



FREE:
GerberViewer for PCBPOOL? customers
Download your free GCPREVUE software
Version 7.0
(3.088 KB)
Newer does not allways mean better! Our customers recommend V7.0.

Version 9.06
(9.633 KB)
Manual for Version 9.06 in PDFFormat

.. find more (newer) versions on the GraphiCode website: www.pcbsino.com.....graphicode.com
Screenshot Version 7.0

Layoutsoftware
TARGET
CAD/CAM Software for PCB schematic and layout.
Beta LAYOUT recommendation!
Format supported by PCBPOOL?.
EAGLE
CAD/CAM Software for PCB schematic and layout.
Free Lightversion available.
Beta LAYOUT recommendation!
Format supported by PCBPOOL?.
PROTEL
CAD/CAM Software for PCB schematic and layout.
30 day trialversion available. Free old DOS Version EasyTrax for download.
Format supported by PCBPOOL?.
PROTEUS
Low cost CAD/CAM Software. Limited Demo Version available.
Format supported by PCBPOOL?.
ORCAD
CAD/CAM Software for PCB schematic and layout.
Format supported by PCBPOOL?.
ULTIBOARD
CAD/CAM Software for PCB schematic and layout.
Limitierte Demo Version erh?ltlich.
Format supported by PCBPOOL?.
SPRINTLAYOUT
CAD/CAM Software for PCB schematic and layout. Limited Demo Version available.
Format supported by PCBPOOL?.
EASY PC
PCB CAD/CAM Software.
Format supported by PCBPOOL?.
EDWIN
CAD/CAM Software for PCB schematic and layout.
Studentversion available.
Format supported by PCBPOOL?.
QUICK ROUTE
CAD/CAM Software for PCB schematic and layout.
Limited Demo Version available.
Format supported by PCBPOOL?.

ARIADNE
PCB CAD/CAM Software from CADUL. Limited Demo Version available.
AUTOENGINEER
PCB CAD/CAM Software from Bartels. Limited Demo Version available.
BPECS32
Very limited PCB CAD software. Limited Demo Version available.
CADint
Swedish CADSoftware for schematics und Layout. Limited Demo Version available.
CADSTAR
CAD/CAM Software for PCB schematic and layout.
CIRCUIT layout
PCB CAD/CAM Software. Limited Demo Version available.
CIRCUIT CREATOR
PCB CAD/CAM Software. Limited Demo Version available.
CIRCAD
PCB CAD/CAM Software. Limited Demo Version available.
CIRCUIT MAKER
CAD/CAM Software for PCB schematic and layout.
Limited Demo Version available.
CSIEDA
WinSchematic, WinPCB, Win3DView, WinGerber, WinSpice, WinSignal. Demo Version available.
DESIGN WORKS
PCB schematic and SimulationsSoftware. Limited Demo Version available.
DREAM CAD
Japanische PCB CAD/CAM Software. Limited Demo Version available.
ECAD
PCB CAD/CAM Software. Limited Demo Version available.
EXPERT PCB
PCB CAD/CAM Software. Limited Demo Version available.
GElectronic
Low cost PCB layout and schematic Software.
LAY01
PCB CAD/CAM Software. Limited Demo Version available.
layout
Windows and MAC PCB CAD/CAM Software. Limited Demo Version available.
MENTOR
CAD/CAM Software for PCB schematic and layout.
MCCAD
PCB CAD/CAM Software. Limited Demo Version available.
OSMOND PPC
Free MAC PCB CAD/CAM Software.
PCB
Free Unix PCB Software.
POWERPCB
PCB CAD/CAM Software. NO limited Demo Version available.
PCB ASSISTANT
Low cost PCB CAD Software. You can download a limited demo version.
PCAD 2001
PCB CAD/CAM Software. 30 day Trialversion available.
PCB ELEGANCE
CAD/CAM Software for PCB schematic and layout.
Limited Demo Version available.
PROBoard, PRONet
Schematic and layout Software for AMIGA Computer.

PCB DESIGNER
Low cost PCB CAD software. Limited Demo Version available.
QCAD
PCB CAD/CAM Software. Limited Demo Version available.
RANGER
PCB CAD/CAM Software. Limited Demo Version available.
SCORE
Free schematicSoftware.
SCOOTER
PCB CAD/CAM Software for Windows and
AtariComputers.
TCI3
Free PCB layout and schematic Software.
VISUALPC
CAD/CAM Software for PCB schematic and layout. Limited Demo Version available.
VUTRAX
PCB CAD/CAM Software. Limited Demo Version available. Tips for Electronic Printed Circuit Board Design
Introduction

This information is presented as guidelines to the preliminary design and development stages of electronic circuits for the purpose of preventing potential electromagnetic interference (EMI) and electromagnetic compatibility (EMC) problems.?The tips are representative of good printed circuit board (PCB) design practices and are recommended as a checklist for evaluating and selecting EMI/EMC software modeling tools.?The EMI simulation of circuit boards requires the evaluation of many details such as clock frequencies, switching rates, rise/fall times, signal harmonics, data transfer rates, impedances, trace loading and consideration of the types and values of the various circuit components.?The physical layout of the PC board and its associated metallic components are important considerations.?Special attention should be given to the placement and characteristics of signal source components, vias, traces, pads, board stackup, shielded enclosures, connectors and cables.?/span> For example, as signal frequencies and clock/switching rates increase, PC board trace characteristics can become similar to those of transmission lines and radiators.牋 A PC board trace or component can become an efficient antenna at a length as small as one twentieth of a wavelength.?

EMI/EMC problems may be approached at the component, PC board or enclosure levels.?However, it is much more efficient to deal with these problems as close to the source or susceptible victim as possible.?Therefore, it is important to consider these tips as guidelines for PCB design and layout so that problems may be identified and prevented prior to actual fabrication of the equipment.

General

(1) EMI controls should be applied at the circuit and box levels prior to addressing EMI at the interconnected and system levels.

(2) Digital circuits are more likely to be the source of emissions due to the handling of periodic waveforms and the fast clock/switching rates.?Analog circuits are more likely to be the susceptible victims due to higher gain functions.

(3) The source or susceptible victim of most EMI problems is typically an electronic component.? Although active components are usually the sources of EMI, passive components often contribute to it, depending on the signal frequencies and component's characteristics. ?For example, an inductor can become predominantly capacitive due to the high frequency parasitic coupling between windings.?A capacitor can develop parasitic series inductance due to its internal inductance and external lead inductance at high fundamental and harmonic frequencies.?

(4) EMI problems involving an active component can be the result of the device's output transferring the emissions or its input providing the path for susceptibility.牋 However, at high frequencies the active component may become a direct radiator or receptor of EMI.?Also, the component抯 power and ground connections can provide paths for both emissions and susceptibility.

(5) Although common mode currents are usually small compared to differential mode currents, they can be the main cause of radiated emissions.

(6) Emissions and susceptibility that are typical in single layer, free wired (using power and ground traces instead of planes) PC Board design, can be greatly improved by using multilayer PC boards with power planes.?High capacitance between a forward signal and its return path (ground plane) provides containment of the electric field.?Low inductance of the paths provides for magnetic flux cancellation.?Although not always realistic in a PCB stackup design, a trace should be spaced one dielectric layer away from its associated return path and the voltage and ground planes should be as closely spaced as possible.

(7) PCB stackup design is important in containing the electromagnetic fields, while providing for additional bypassing and decoupling of the power bus and minimizing bus voltage transients.?Some of the benefits of multilayer PC board design with power planes are:?

a. The power planes, if properly designed, will provide an image plane effect.?Since the return currents in the power planes are equal and opposite polarity to the associated signal currents, their electromagnetic fields will tend to cancel.?Power planes can also reduce the loop areas of signal and power traces, resulting in a decrease of EMI emissions and susceptibility.?

b. A ground plane can lower the overall ground impedance, thus reducing high frequency ground bounce.?Also, the impedance between the ground and voltage planes is lowered at the high frequencies and this reduces power bus ringing.?

(8) Clocked IC抯 with rapid output transitions can be very demanding on voltage and current distribution components such as the power supply, power bus, and power planes.?The inductance of the power bus can prevent the rapid energy transfer needed to meet the quick output transitions and fast rise times.?This can be improved with the placement of decoupling capacitors at the IC抯 power pins.?The capacitors must be properly selected in their frequency response to deliver the energy needed at the IC抯 output frequency spectrum.?However, as the number of decoupling paths increase, so do the number of voltage drops across them and this can result in power bus transients along with the associated common mode emissions.牋 This problem can be minimized with proper power plane design in the area of the IC抯.?The power plane acts as an effective high frequency capacitor, and consequently, as an additional energy source needed for cleaner IC outputs.牋?

PCB Layout

(1) Use multilayer PC boards rather than singlelayer boards whenever possible.

(2) If a single layer board must be used, a ground plane should be utilized to help reduce radiation.

(3) Top and bottom ground planes can help reduce radiation from multilayer boards by at least 10 dB.

(4) Segmented PC board ground planes are useful for reducing cable radiation due to common mode currents.

(5) Power and return planes should be located on opposite sides of a multilayer PCB.?Effective power planes are low in inductance.? Therefore, any transients that may develop on the power planes will be at lower levels, resulting in lower common mode EMI.

(6) Connection of the power planes to high frequency IC power pins should be as close to the IC pins as possible.?Faster rise times may require connections directly to the pads of the IC power pins.

(7) Analog and digital circuits are susceptible to interaction when located in close proximity to each other.?These should be located on different layers of the PC board whenever possible.?If the circuits must be located on the same layer, they should be separated into analog and digital areas with proper isolation layout.

(8) High frequency traces, such as those used for clock and oscillator circuits, should be contained by two ground planes.?This provides for maximum isolation.?The reactance of a trace or conductor can easily exceed its dc resistance as frequency increases.?If this trace is run close to its ground plane, the inductance can be reduced by about one third.牋

(9) Additional EMI preventive measures for clock/oscillator traces include the utilization of guard traces grounded to the ground plane at several locations. The shielding of clock and oscillator components with foil or small metallic enclosures may also be needed.

(10) Overall circuit crosstalk increases by a factor of two whenever the clock rate is doubled.牋 EMI radiation and crosstalk may be reduced by minimizing the PC board trace height above the ground plane.?

(11) PC board edge radiation may be the result of traces being located too close to the board edge.?This can be minimized by keeping traces at a distance of at least 3 times the board thickness away from the board edge.?

(12) PC board trace stacking should be avoided if possible.?Otherwise, it should be limited to one trace height in order to reduce radiation, crosstalk and impedance mismatches.

(13) Parallel traces are often susceptible to crosstalk.?These should be separated by at least 2 trace widths for crosstalk reduction.

Decoupling, Bypassing and Filtering

(1) EMI filters can be used as a shunt element to divert electrical currents from a trace or conductor; as a series element to block a trace or conductor current; or they may be used as a combination of these functions.?Selection of the filter elements should always be based on the desired frequency range and component characteristics.?A low pass filter can be useful for reducing most high frequency EMI problems.?It incorporates a capacitive shunt and series resistance or inductance.? However, at frequency extremes, the capacitor can become inductive and the inductor can become capacitive causing the filter to act more like a bandstop filter.牋 The filter design type should be based on the overall impedance at the circuit抯 point of application for proper match.?A Tfilter design is effective for most EMI applications and is ideal for analog and digital I/O ports.牋?

(2) Capacitors may be used for signal filtering and power source decoupling within their high frequency performance characteristics.?However, their internal and external inductance can limit performance at high frequencies.?Ceramic capacitors are recommended for the high frequencies, particularly those in the GHz range.?A capacitor providing a reactance of less than 1 Ohm at the frequency of concern should suffice.牋 Capacitor lead and trace lengths must be short at the high frequencies in order to prevent the addition of inductive reactance.

(3) PC board bypass capacitors used at high frequencies (greater than 100 MHz) should utilize surface mount technology (SMT) with vias close enough to the mounting pad to minimize or eliminate the traces.?The via holes should be large (greater than .035 inch in diameter) and the PC board should be thin enough to bring power and ground planes near the body of the capacitor (less than .030 inch thick).牋 Proper design layout of the bypass capacitors can greatly reduce the power and ground circuit noise by lowering the overall effective inductance of the capacitors.

(4) Wire wound ferrite inductors may be used for EMI emissions and immunity filtering at lower RF frequencies.?These can supply from about 1 microhenry to 1 millihenry of inductance.牋 However, they can become a capacitor above their resonant frequency and are useless in the most common EMI frequency range of 50 MHz to 500 MHz.?Ferrites and ferrite beads are recommended for higher frequency applications where they become lossy and act more like a resistor.?Select a ferrite impedance of about 100 to 600 Ohms at the frequencies of concern.

(5) Shielded I/O cable connectors equipped with bypass capacitors or filter pins should be used whenever possible.

(6) I/O filters should be inside of the I/O connector (as with filter pins) instead of on the PC board.

(7) I/O bypass capacitors should be mounted at the I/O connector instead of on the PC board.

(8) I/O ferrites should be mounted inside of the I/O connector instead of on the PC board.

(9) A snapon ferrite bead at the I/O cable connector can provide 3 to 5 dB of common mode absorption.

(10) Multiple ferrites may be used to reduce radiation by up to 10 dB depending on their characteristics at the frequency of interest.

(11) Ferrite beads are available in highQ resonant and lowQ nonresonant (absorptive) types.?The lowQ beads are recommended for digital circuits and filtering applications.牋?

(12) External cable or I/O connector filters can provide for a common mode rejection of greater than 10 dB.

Cables and Connectors

(1) Cables should be grouped according to their function such as power, analog, digital, and RF.

(2) Separate connector assemblies should be used for analog and digital signals.

(3) Analog and digital connectors should be located as far apart as possible.

(4) Analog and digital signal pins should be separated by unused grounded pins when sharing the same I/O connector.

(5) Individual pins should be used inside the I/O connector for each signal return so that all return circuits remain separated.

(6) Connector crosstalk may be reduced by using separate power and ground pins for each signal and by reducing the circuit抯 loading and current flow.牋?

(7) Cable shields should be grounded to equipment housing at the I/O points.

(8) Shielded I/O cables are most effective if grounded at both ends.

(9) Cable common mode currents should be removed at the equipment抯 metal housing prior to internal connections.

(10) Cables should be routed close to ground planes, shielded structures, and cable trays.

Grounding

(1) Use ground planes instead of vectorial traces.

(2) Ground traces should be as short and thick as possible.

(3) Decouple signal and RF circuit grounds.