Practical Transmission Line Design and Measurement: Lossless Single-ended Transmission Lines

Practical Guide to Transmission Line Design and Characterization for Signal Integrity Applications
	Table of Contents
	Chapter 1 What Are Transmission Lines and Why You Should Care
		1.1 Do We Really Need Another Transmissi
		1.2 All Interconnects Are Transmission L
		1.3 The Importance of Measurement or Cha
		1.4 When Are Interconnects Not Transpare
		1.5 Why the RF World is Different from t
		1.6 Review Questions
	Chapter 2 Essential Principles of Signal on Interconnects
		2.1 All Interconnects are Transmission Lines
		2.2 Signals Are Dynamic
		2.3 A Simple Free Tool to Illustrate the Propagation of a Signal
		2.4 Time Delay and Wiring Delay
		2.5 Signals See an Instantaneous Impedance
		2.6 Instantaneous Impedance and Characteristic
Impedance
		2.7 What Happened to the Inductance of the Transmission Line?
		2.8 What is Special about 50 Ohms?
		2.9 The Paradox of Current Flow into a Transmission Line
		2.10 Displacement Current as a New Type of Current
		2.11 Return Current in a Transmission Line
		2.12 Where Does the Return Current Flow?
		2.13 Review Questions
	Chapter 3 Categorizing Transmission Lines
		3.1 Distinguishing Metrics
		3.2 Uniform or Nonuniform Transmission Lines
		3.3 Single-Ended or Differential
		3.4 Uncoupled or Coupled
		3.5 Lossless and Lossy Transmission Lines
		3.6 Balanced or Unbalanced
		3.7 Review Questions
	Chapter 4 Five Impedances of a Transmission Line
		4.1 The Instantaneous Impedance
		4.2 Characteristic Impedance
		4.3 The Surge or Wave Impedance
		4.4 The Input Impedance in the Time Domain
		4.5 Drawing Circuits with Resistors and Transmission Lines
		4.6 Input Impedance in the Frequency Domain
		4.7 A Few Special Cases for the Input Impedance in the Frequency Domain
		4.8 Which is Better, the Frequency or the Time
Domain Impedance?
		4.9 Review Questions
	Chapter 5 Why We Care About Impedance: Reflections
		5.1 Reflections Keep the Universe from Blowing Up
		5.2 The Reflection and Transmission Coefficient
		5.3 Using the Reflection Coefficient and Transmission Coefficient
		5.4 An Important Distinction Between the Signal and the Voltage
		5.5 Important Termination Special Case: A 50-Ohm Resistive Load
		5.6 Important Termination Special Case:
		5.7 Important Termination Case: A Short
		5.8 Resolving the Paradox: Where Did 2V
		5.9 Another Paradox: The Signal Launched into the Transmission Line
		5.10 Review Questions
	Chapter 6 Analyzing Reflections with the Bounce Diagram
		6.1 A Typical TX-RX Circuit
		6.2 The Bounce Diagram: An Example
		6.3 Simulating the Dynamic Nature of Reflections
		6.4 Special Case: Short at the Far End
		6.5 Circuits with an Interface between Two Tranmission Lines
		6.6 Try These Examples of Transmission Line Circuits
		6.7 Review Questions
	Chapter 7 Practical Applications of
Transmission Line Properties:
What Every Scope User Needs to
Know about Transmission Line
s
		7.1 A Commonly Misinterpreted Effect
		7.2 The Wrong Root Causes of Rise Time Increase with Cable Length
		7.3 Modeling Any Transient Source with Three Figures of Merit
		7.4 Analyzing the Long Rise Time in Terms of Transmission Lines
		7.5 The Third Figure of Merit for all Sources: Intrinsic Rise Time
		7.6 When the Source Impedance is 50 Ohms
		7.7 When the Thevenin Source Resistance is Much Lower than 50 Ohms
		7.8 When to Use 50 Ohms or 1-Mohm Input to Scope
		7.9 Review Questions
	Chapter 8 Electrical Models of Transmission Lines
		8.1 Measured Electrical Behaviors of Transmission Lines
		8.2 Equivalent Electric Circuit Models of Transmission Lines
		8.3 Models and the Real World
		8.4 Real and Ideal Transmission Lines
		8.5 Introducing a Simple, Open-Source SPICE-Like Simulators: QUCS
		8.6 The Tline Element and Real Transmission Lines
		8.7 Total L and C in a Transmission Line
		8.8 The Limit to a Transmission Line as a Lumped C or L
		8.9 Capacitance Per Length and Inductance Per Length
		8.10 Limitations of the n-Section Lumped Circuit Model
		8.11 Review Questions
	Chapter 9 The TDR Principles
		9.1 A Simple Example of a TDR Measurement and What It Can Measure
		9.2 Principles of Operation
		9.3 From Reflection Coefficient to Impedence
		9.4 TDR Response with a Short Discontinuity Before the Termination
		9.5 The TDR Response from Resistors
		9.6 A Uniform Transmission Line or a Resistor?
		9.7 Electrically Long and Electrically Short Transmission Lines
		9.8 Spatial Resolution of a TDR
		9.9 Masking: Reflections from Two Uniform Transmission Lines
		9.10 Review Questions
	Chapter 10 Practical TDR Measurements
		10.1 Always Use a Torque Wrench
		10.2 Cable Termination Launches
		10.3 Quality of Cables
		10.4 Uniform Transmission Lines and Impedance
		10.5 How Uniform Are Transmission Lines?
		10.6 Increasing Impedance Down the Line
		10.7 Discontinuities from Different Ends
		10.8 TDR Response from a Transmission Line with an Open or Short Far End
		10.9 TDR Response from a Very Low Impedance Transmission Line
		10.10 When There is Coupling to a High Q Resonator
		10.11 Review Questions
	Chapter 11 Measuring Dk with a TDR
		11.1 The Dk and the Speed of a Signal
		11.2 Dkeff of Microstrip and Stripline
		11.3 Measuring Dk, Method 1: Guess the Location of the Ends of the Line
		11.4 Measuring Dk, Method 2: Two Different Line Lengths
		11.5 Measuring Dk, Method 3: Special Test Structure with Small Pads
		11.6 From Effective Dk to Bulk Dk in Micostrop
		11.7 At What Frequency Does the TDR Measure the Impedance or Dielectric Constant?
		11.8 Review Questions
	Chapter 12 Calculating the Characteristic Impedance from
Geometry and Material Properties
		12.1 Characteristic Impedance and Geometry
		12.2 Analytical Exact Examples
		12.3 Using a 2D Field Solver to Calculate the Characteristic Impedance
		12.4 Finite Width of the Return Path
		12.5 Practice Safe Simulation and Rule #9
		12.6 Review Questions
	Chapter 13 A Microstrip Transmission Line
		13.1 The Surface Microstrip
		13.2 A Simple Rule of Thumb
		13.3 Sensitivity Analysis: First- and Second-Order Factors
		13.4 A Comparison to Analytical Approximations
		13.5 Comparison to a Measurements of a Simple Test Board
		13.6 Second-Order Factors: Solder Mask, Trace Thickness, Etchback, and Adjacent Conductors
		13.7 Review Questions
	Chapter 14 Stripline Analysis
		14.1 Simple Stripline Analysis
		14.2 Comparison to Analytical Approximations
		14.3 A Design Example for Asymmetric Strpline
		14.4 When Does the Top Plane Not Matter?
		14.5 First- and Second-Order Factors
		14.6 Review Questions
	Chapter 15 Differential Signaling and Differential Impedance
		15.1 Differential Pairs for Low-Noise Analog Signals
		15.2 Differential and Common Signals in High Speed Digital Signaling
		15.3 Differential and Common Impedance with Traces Far Apart
		15.4 Calculated Differential and Common Impedances with No Coupling
		15.5 Displacement Current and the Origin of Impedance
		15.6 Impedance of One Line When Part of a Pair
		15.7 Case 1: The Second Line is Kept Low
		15.8 Case 2: The Second Line is Driven with an Opposite Signal
		15.9 Case 3: The Second Line is Driven with the Same Signal
		15.10 Odd and Even Modes and Impedance
		15.11 Important Properties of Odd- and Even-Mode Impedances
		15.12 Relating Odd-Mode, Even-Mode Impedance, and Differential and Common Impedance
		15.13 How Not to be Confused about Differential Impedance
		15.14 Review Questions
	Chapter 16 Differential TDR
		16.1 Measuring the Odd-Mode Impedance
		16.2 Differential Impedance for a Tightly Coupled Differential Pair
		16.3 Changing Coupling with Constant Linewidth
		16.4 Changing Coupling with Constant Differential Impedance
		16.5 Impedance Profile of a Very Tightly Coupled Differential Pair
		16.6 Review Questions
	Chapter 17 Exploring the Properties of Differential Pairs
		17.1 Engineering a Microstrip with a Constant Differential Impedance
		17.2 Which is Better: Tightly Coupled or Loosely Coupled Differential Pairs?
		17.3 Speed of a Differential and Common Signal
		17.4 Stripline First-Order Factors
		17.5 Stripline Second-Order Factors
		17.6 Review Questions
	Chapter 18 Differential Pairs with No Return Paths
		18.1 The Single-Ended Impedance and Location of the Return Plane
		18.2 The Common Impedance and Location of the Return Path
		18.3 Coupling Between the p- and n-Lines and the Return Plane
		18.4 Differential Impedance of a Differential Pair and Location of the Return Plane
		18.5 Return Currents in a Differential Pair with the Plane Far Away
		18.6 TDR Response of a Differential Pair with a Short Gap in the Return Plane
		18.7 TDR Response of a Differential Pair with a Short Gap in the Return Plane
		18.8 TDR Response
		18.9 Review Questions
	Chapter 19 Analyzing Discontinuities and Hacking Interconnects
		19.1 Electrically Short Interconnects as Discontinuities
		19.2 Hacking Interconnects
		19.3 The Simulation Environment: QUCS
		19.4 QUCS Schematics Available for Download
		19.5 Simulating a TDR
		19.6 Models of Discontinuities
		19.7 An Example of Hacking an Interconnect with a Launch Discontinuity (Schematic File G_LaunchC)
		19.8 Avoid Mink Holes
		19.9 Hacking an Interconnect with Multiple Impdances
		19.10 A Transmission Line with a Small Capacitive Discontinuity
		19.11 Hacking a Very Low Impedance Interconnect
		19.12 Extracting Circuit Models for Termination Resistors
		19.13 Review Questions
	Appendix A: Answers to the Review Questions
		Chapter 1
		Chapter 2
		Chapter 3
		Chapter 4
		Chapter 5
		Chapter 6
		Chapter 7
		Chapter 8
		Chapter 9
		Chapter 10
		Chapter 11
		Chapter 12
		Chapter 13
		Chapter 14
		Chapter 15
		Chapter 16
		Chapter 17
		Chapter 18
		Chapter 19
	References
	About the Author