Introduction
Why signal integrity matters • Noise margin and noise sources • Reasons for board spins
Transmission Lines
Ideal transmission lines • Lossy transmission lines • Terminology • Calculating impedance • Dialectric constant of prepreg and laminates • Measuring impedance • Why 50 ohms?
Reflections
Formulas • Recognizing low vs high source impedance • What is reflection and what is ringing?
Termination Techniques
Unterminated transmission lines • Parallel, series and RC termination • Why terminate? • When to terminate • Power consumption of termination
Net Topologies
Multi-node nets •: Where to terminate • One vs. multiple drivers • One vs. multiple loads • Handling of connectors
IBIS Simulation
Understanding the models • Process corner simulation • When IBIS simulation is not possible
Stubs
Termination stubs • Understanding the quarter wavelength stub
Bus Structures
PCI bus • SSTL termination • DDR1, DDR2, DDR3, DDR4 schemes • LVDS bus • Typical address and data bus simulation
Crosstalk
Near-end vs. far-end crosstalk • Capacitive vs. inductive coupling • Critical length • Reducing crosstalk • Broadside vs. side-by-side • Guard traces • Reference plane
Differential Signalling
Principle for differential signalling • Advantages and disadvantages • Cable vs. on the board • Immune to common mode coupling? • Does differential routing make sense?
Power Sub-System
Power distribution model • Voltage ripple requirements • Noise margin considerations
Bypass Caps
Capacitor types • Ceramics • RLC models • Multi-terminal capacitors • Bulk capacitors • Land patterns • Effective inductance • Placement around vs. on the back side of a board • Interplane capacitance • Myths about bypass
Designing a Power Distribution Network (PDN)
Concept for finding the right amount of bypass • Spreadsheet simulation • PDN tool • Frequency range • Package model • On-package and on-die capacitance • Via inductance • Defining plane requirements
Testing the PDN
Test methods • Required equipment • Understanding the test setup and results • Preparing for doing the tests in your lab
Vcc & Ground Bounce
Defining vcc bounce, ground bounce and SSN • Measuring ground bounce • Package lead inductance • Simple paper estimation • Finding peak I/O current • Simulating SSN with an IBIS simulator
Noise Margin Budget
Understanding noise sources on the board • Reflections • Crosstalk • SSN • Power supply variations • Ground offsets • Trace voltage drops and losses • Terminator noise • Skin effect • Dialectric loss • PCI Express example • Vtt example
Creating Routing Rules
Design flow • Building a design rule set • Efficient pre and post layout review technique
Differential signalling
Skew and jitter • Loss impact on multi gigabit differential signalling • Pre/de-emphasis and receiver equalization
PCB Materials
Understanding PCB materials • Copper • Prepreg and laminates • Selecting surface finish
PCB Stack-Up
Defining the PCB stack-up • Building a design rule set • Efficient pre and post layout review technique
PCB Test Features
Specifying the PCB stack-up • Materials • Patents • Test features for layer order • Test traces • Test points and probes for high-speed
Vias and Models
Via types • Non-functional pads • Capacitance and inductance • Is the via a stub? • Via models • Understanding CAF • Backdrilling
