Book Description
Consistently Design PDNs That Deliver Reliable Performance at the Right Cost
Too often, PDN designs work inconsistently, and techniques that work in some scenarios seem to fail inexplicably in others. This book explains why and presents realistic processes for getting PDN designs right in any new product. Drawing on 60+ years of signal and power integrity experience, Larry Smith and Eric Bogatin show how to manage noise and electrical performance, and complement intuition with analysis to balance cost, performance, risk, and schedule. Throughout, they distill the essence of complex realworld problems, quantify core principles via approximation, and apply them to specific examples. For easy usage, dozens of key concepts and observations are highlighted as tips and listed in quick, chapterending summaries.
Coverage includes
• A practical, starttofinish approach to consistently meeting PDN performance goals
• Understanding how signals interact with interconnects
• Identifying root causes of common problems, so you can avoid them
• Leveraging analysis tools to efficiently explore design space and optimize tradeoffs
• Analyzing impedancerelated properties of series and parallel RLC circuits
• Measuring low impedance for components and entire PDN ecologies
• Predicting loop inductance from physical design features
• Reducing peak impedances from combinations of capacitors
• Understanding power and ground plane properties in the PDN interconnect
• Taming signal integrity problems when signals change return planes
• Reducing peak impedance created by ondie capacitance and package lead inductance
• Controlling transient current waveform interactions with PDN features
• Simple spreadsheetbased analysis techniques for quickly creating firstpass designs
This guide will be indispensable for all engineers involved in PDN design, including product, board, and chip designers; system, hardware, component, and package engineers; power supply designers, SI and EMI engineers, sales engineers, and their managers.
Table of Contents
 About This EBook
 Title Page
 Copyright Page
 Contents at a glance
 Contents
 Preface
 Acknowledgments
 About the Authors
 Chapter 1 Engineering the Power Delivery Network

Chapter 2 Essential Principles of Impedance for PDN Design
 2.1 Why Do We Care About Impedance?
 2.2 Impedance in the Frequency Domain
 2.3 Calculating or Simulating Impedance
 2.4 Real Circuit Components vs. Ideal Circuit Elements
 2.5 The Series RLC Circuit
 2.6 The Parallel RLC Circuit
 2.7 The Resonant Properties of a Series and Parallel RLC Circuit
 2.8 Examples of RLC Circuits and Real Capacitors
 2.9 The PDN as Viewed by the Chip or by the Board
 2.10 Transient Response
 2.11 Advanced Topic: The Impedance Matrix
 2.12 The Bottom Line
 References

Chapter 3 Measuring Low Impedance
 3.1 Why Do We Care About Measuring Low Impedance?
 3.2 Measurements Based on the V/I Definition of Impedance
 3.3 Measuring Impedance Based on the Reflection of Signals
 3.4 Measuring Impedance with a VNA
 3.5 Example: Measuring the Impedance of Two Leads in a DIP
 3.6 Example: Measuring the Impedance of a Small Wire Loop
 3.7 Limitations of VNA Impedance Measurements at Low Frequency
 3.8 The FourPoint Kelvin Resistance Measurement Technique
 3.9 The TwoPort Low Impedance Measurement Technique
 3.10 Example: Measuring the Impedance of a 1inch Diameter Copper Loop
 3.11 Accounting for Fixture Artifacts
 3.12 Example: Measured Inductance of a Via
 3.13 Example: Small MLCC Capacitor on a Board
 3.14 Advanced Topic: Measuring OnDie Capacitance
 3.15 The Bottom Line
 References

Chapter 4 Inductance and PDN Design
 4.1 Why Do We Care About Inductance in PDN Design?
 4.2 A Brief Review of Capacitance to Put Inductance in Perspective
 4.3 What Is Inductance? Essential Principles of Magnetic Fields and Inductance
 4.4 Impedance of an Inductor
 4.5 The QuasiStatic Approximation for Inductance
 4.6 Magnetic Field Density, B
 4.7 Inductance and Energy in the Magnetic Field
 4.8 Maxwell’s Equations and Loop Inductance
 4.9 Internal and External Inductance and Skin Depth
 4.10 Loop and Partial, Self and Mutual Inductance
 4.11 Uniform Round Conductors
 4.12 Approximations for the Loop Inductance of Round Loops
 4.13 Loop Inductance of Wide Conductors Close Together
 4.14 Approximations for the Loop Inductance of Any Uniform Transmission Line
 4.15 A Simple Rule of Thumb for Loop Inductance
 4.16 Advanced Topic: Extracting Loop Inductance from the Sparameters Calculated with a 3D Field Solver
 4.17 The Bottom Line
 References

Chapter 5 Practical MultiLayer Ceramic Chip Capacitor Integration
 5.1 Why Use Capacitors?
 5.2 Equivalent Circuit Models for Real Capacitors
 5.3 Combining Multiple Identical Capacitors in Parallel
 5.4 The Parallel Resonance Frequency Between Two Different Capacitors
 5.5 The Peak Impedance at the PRF
 5.6 Engineering the Capacitance of a Capacitor
 5.7 Capacitor Temperature and Voltage Stability
 5.8 How Much Capacitance Is Enough?
 5.9 The ESR of Real Capacitors: First and SecondOrder Models
 5.10 Estimating the ESR of Capacitors from Spec Sheets
 5.11 Controlled ESR Capacitors
 5.12 Mounting Inductance of a Capacitor
 5.13 Using VendorSupplied Sparameter Capacitor Models
 5.14 How to Analyze VendorSupplied SParameter Models
 5.15 Advanced Topics: A Higher Bandwidth Capacitor Model
 5.16 The Bottom Line
 References

Chapter 6 Properties of Planes and Capacitors
 6.1 The Key Role of Planes
 6.2 LowFrequency Property of Planes: Parallel Plate Capacitance
 6.3 LowFrequency Property of Planes: Fringe Field Capacitance
 6.4 LowFrequency Property of Planes: Fringe Field Capacitance in Power Puddles
 6.5 Loop Inductance of Long, Narrow Cavities
 6.6 Spreading Inductance in Wide Cavities
 6.7 Extracting Spreading Inductance from a 3D Field Solver
 6.8 LumpedCircuit Series and Parallel SelfResonant Frequency
 6.9 Exploring the Features of the Series LC Resonance
 6.10 Spreading Inductance and Source Contact Location
 6.11 Spreading Inductance Between Two Contact Points
 6.12 The Interactions of a Capacitor and Cavities
 6.13 The Role of Spreading Inductance: When Does Capacitor Location Matter?
 6.14 Saturating the Spreading Inductance
 6.15 Cavity Modal Resonances and Transmission Line Properties
 6.16 Input Impedance of a Transmission Line and Modal Resonances
 6.17 Modal Resonances and Attenuation
 6.18 Cavity Modes in Two Dimensions
 6.19 Advanced Topic: Using Transfer Impedance to Probe Spreading Inductance
 6.20 The Bottom Line
 References

Chapter 7 Taming Signal Integrity Problems When Signals Change Return Planes
 7.1 Signal Integrity and Planes
 7.2 Why the Peak Impedances Matter
 7.3 Reducing Cavity Noise through Lower Impedance and Higher Damping
 7.4 Suppressing Cavity Resonances with Shorting Vias
 7.5 Suppressing Cavity Resonances with Many DC Blocking Capacitors
 7.6 Estimating the Number of DC Blocking Capacitors to Suppress Cavity Resonances
 7.7 Determining How Many DC Blocking Capacitors Are Needed to Carry Return Current
 7.8 Cavity Impedance with a Suboptimal Number of DC Blocking Capacitors
 7.9 Spreading Inductance and Capacitor Mounting Inductance
 7.10 Using Damping to Suppress Parallel Resonant Peaks Created by a Few Capacitors
 7.11 Cavity Losses and Impedance Peak Reduction
 7.12 Using Multiple Capacitor Values to Suppress Impedance Peak
 7.13 Using Controlled ESR Capacitors to Reduce Peak Impedance Heights
 7.14 Summary of the Most Important Design Principles for Managing Return Planes
 7.15 Advanced Topic: Modeling Planes with Transmission Line Circuits
 7.16 The Bottom Line
 References

Chapter 8 The PDN Ecology
 8.1 Putting the Elements Together: The PDN Ecology and the Frequency Domain
 8.2 At the HighFrequency End: The OnDie Decoupling Capacitance
 8.3 The Package PDN
 8.4 The Bandini Mountain
 8.5 Estimating the Typical Bandini Mountain Frequency
 8.6 Intrinsic Damping of the Bandini Mountain
 8.7 The Power Ground Planes with Multiple Via Pair Contacts
 8.8 Looking from the Chip Through the Package into the PCB Cavity
 8.9 Role of the Cavity: Small Boards, Large Boards, and “Power Puddles”
 8.10 At the Low Frequency: The VRM and Its Bulk Capacitor
 8.11 Bulk Capacitors: How Much Capacitance Is Enough?
 8.12 Optimizing the Bulk Capacitor and VRM
 8.13 Building the PDN Ecosystem: The VRM, Bulk Capacitor, Cavity, Package, and OnDie Capacitance
 8.14 The Fundamental Limits to the Peak Impedance
 8.15 Using One Value MLCC Capacitor on the BoardGeneral Features
 8.16 Optimizing the Single MLCC Capacitance Value
 8.17 Using Three Different Values of MLCC Capacitors on the Board
 8.18 Optimizing the Values of Three Capacitors
 8.19 The Frequency Domain Target Impedance Method (FDTIM) for Selecting Capacitor Values and the Minimum Number of Capacitors
 8.20 Selecting Capacitor Values with the FDTIM
 8.21 When the OnDie Capacitance Is Large and Package Lead Inductance Is Small
 8.22 An Alternative Decoupling Strategy Using Controlled ESR Capacitors
 8.23 OnPackage Decoupling (OPD) Capacitors
 8.24 Advanced Section: Impact of Multiple Chips on the Board Sharing the Same Rail
 8.25 The Bottom Line
 References

Chapter 9 Transient Currents and PDN Voltage Noise
 9.1 What’s So Important About the Transient Current?
 9.2 A Flat Impedance Profile, a Transient Current, and a Target Impedance
 9.3 Estimating the Transient Current to Calculate the Target Impedance with a Flat Impedance Profile
 9.4 The Actual PDN Current Profile Through a Die
 9.5 ClockEdge Current When Capacitance Is Referenced to Both Vss and Vdd
 9.6 Measurement Example: Embedded Controller Processor
 9.7 The Real Origin of PDN Noise–How ClockEdge Current Drives PDN Noise
 9.8 Equations That Govern a PDN Impedance Peak
 9.9 The Most Important Current Waveforms That Characterize the PDN
 9.10 PDN Response to an Impulse of Dynamic Current
 9.11 PDN Response to a Step Change in Dynamic Current
 9.12 PDN Response to a Square Wave of Dynamic Current at Resonance
 9.13 Target Impedance and the Transient and AC SteadyState Responses
 9.14 Impact of Reactive Elements, qFactor, and Peak Impedances on PDN Voltage Noise
 9.15 Rogue Waves
 9.16 A Robust Design Strategy in the Presence of Rogue Waves
 9.17 ClockEdge Current Impulses from Switched Capacitor Loads
 9.18 Transient Current Waveforms Composed of a Series of Clock Impulses
 9.19 Advanced Section: Applying Clock Gating, Clock Swallowing, and Power Gating to Real CMOS Situations
 9.20 Advanced Section: Power Gating
 9.21 The Bottom Line
 References

Chapter 10 Putting It All Together: A Practical Approach to PDN Design
 10.1 Reiterating Our Goal in PDN Design
 10.2 Summary of the Most Important Power Integrity Principles
 10.3 Introducing a Spreadsheet to Explore Design Space
 10.4 Lines 1–12: PDN Input Voltage, Current, and Target Impedance Parameters
 10.5 Lines 13–24: 0th Dip (ClockEdge) Noise and OnDie Parameters
 10.6 Extracting the Mounting Inductance and Resistance
 10.7 Analyzing Typical Board and Package Geometries for Inductance
 10.8 The Three Loops of the PDN Resonance Calculator (PRC) Spreadsheet
 10.9 The Performance Figures of Merit
 10.10 Significance of Damping and qfactors
 10.11 Using a Switched Capacitor Load Model to Stimulate the PDN
 10.12 Impulse, Step, and Resonance Response for ThreePeak PDN: Correlation to Transient Simulation
 10.13 Individual qfactors in Both the Frequency and Time Domains
 10.14 Rise Time and Stimulation of Impedance Peak
 10.15 Improvements for a ThreePeak PDN: Reduced Loop Inductance of the Bandini Mountain and Selective MLCC Capacitor Values
 10.16 Improvements for a ThreePeak PDN: A Better SMPS Model
 10.17 Improvements for a ThreePeak PDN: OnPackage Decoupling (OPD) Capacitors
 10.18 Transient Response of the PDN: Before and After Improvement
 10.19 Reexamining Transient Current Assumptions
 10.20 Practical Limitations: Risk, Performance, and Cost Tradeoffs
 10.21 Reverse Engineering the PDN Features from Measurements
 10.22 SimulationtoMeasurement Correlation
 10.23 Summary of the Simulated and Measured PDN Impedance and Voltage Features
 10.24 The Bottom Line
 References
 Index
Product Information
 Title: Principles of Power Integrity for PDN DesignSimplified: Robust and Cost Effective Design for High Speed Digital Products
 Author(s):
 Release date: March 2017
 Publisher(s): Pearson
 ISBN: 9780132735568