About the Training Course

This is an advanced-level training course for experienced digital designers who want to press their designs to the upper limits of speed and distance.
Focusing on lossy transmission environments like backplanes, cables and long on-chip interconnections, this training course teaches a unified theory of transmission impairments that apply to any transmission media. Topics include: skin effect and dielectric loss, on-chip vs. off-chip transmission-line behavior, equalization, serial interconnections, lossy media, single-ended and differential signaling, frequency-domain modeling, signal distribution and clock jitter.
This training course is an advanced sequel to High-Speed Digital Design by Dr Howard Johnson.
All delegates receive a free copy of Howard Johnson's "High-Speed Signal Propagation - Advanced Black Magic" (Prentice Hall)

Course Benefits

• This is a practical course, filled with practical examples and explanations.
• Delegates without the benefit of formal training in analog circuit theory can use and apply the formulas and examples from this training course to determine which of their circuits will encounter difficulties and how to fix them.
• Delegates who have completed (at least) a first-year university level class in introductory linear circuit theory will comprehend the material at a deeper level.

Questions & Comments: all students who attend our High-Speed Digital Design training courses have the opportunity to talk directly with Dr. Johnson.

Who is this training course for?

This is an advanced University based training course for Digital logic engineers, chip designers, system architects, EMC specialists, and applications engineers; anyone working with digital logic at speeds in excess of 1 GHz.

Training Course Content

Fundamentals of Time and Frequency

• Characterize the types of simulation tools available to help you in your design, including the division between linear and non-linear analysis
• Review relations among time, frequency, and the physical extent of a circuit, including rules for dimensional scaling
• Introduce a theorem about maximal resonance

Lossy Transmission Line Parameters

• Model a transmission structure using a cascade of simple linear elements
• Define the characteristic impedance and propagation function
• Trace the flow of returning signal current on an ideal, lossless transmission line
• Calculate DC resistance
• Evaluate AC resistance including skin effect, proximity effect and surface roughness
• Investigate dielectric losses
• Define two-port S-parameter representations of transmission structures, and show how they are used to compute system response

Classroom demonstration: A transmission line is always a transmission line

Performance Regions: On-chip vs. Off-chip

• Present the standard copper performance model
• Explore the hierarchy of transmission-line performance regions
• Study the lumped-element region, useful for understanding small interconnections and transmission-line imperfections
• On-chip connections use the RC region
• PCB interconnections use the skin-effect and dielectric-loss-limited regions
• Show the similarities and differences among the various regions
• Check conditions for existence of undesirable non-TEM modes
• Discuss the need for equalization, and show examples of equalizer circuits
• Investigate DC wander and circuits for DC restoration

Example waveforms: 10 Gb/s serial link with PAM-4 coding and fully adaptive equalizer

PCB Trace Design and Connectors

• Dissect microstrip and stripline design tables
• Consider the effects of nickel plating and soldermask coating
• Estimate limits to the attainable length of a pcb trace operated at extreme speeds
• Compute the effects of impedance discontinuities caused by stubs and loads and learn to counteract these effects
• Characterize connectors
• Introduce the concept of tapering necessary for certain SMA connector applications
• Scrutinize the capacitance and inductance of a via, including the effect of pad-stripping, back-drilling, blind vias, and dangling via stubs

Classroom demonstration: proximity effect for differential stripline traces

Classroom video: experiment showing inductance of vias, and effect of distance to the nearest inter-plane connection

Differential Signaling

• Define differential and common-mode voltages, currents, impedance and differential S-parameters
• Present design tables for both edge-coupled and broadside-coupled differential traces
• Cite the specific advantages of differential signaling including improved tolerance to ground shifts, reduced radiation, and better tolerance of high-frequency losses
• Discuss management of differential skew

Clock Distribution and Jitter

• Review special requirements for clock signaling including low skew
• Consider means of attaining exceptionally low skew
• Emphasize the importance of terminating clock lines
• Provide advice on routing differential clocks
• Show why serpentine delays (source one from loads multiple driving for strategies) often deliver poor results
• Discuss the general issue of distributing high-quality signals to multiple loads
• Show how to construct and test a proper daisy-chain, "T", or "H" distribution
• Define clock jitter, clock jitter propagation, methods for measuring jitter, and the emerging issue of random versus deterministic jitter budgeting

References

"Very practical! Real situations that exist at work. This analysis will save us as things go faster."
Arthur Woo, Design Engineer, Hewlett Packard Laboratories
"Extremely good presenter, very practically minded research."
Matt Oseman, Senior Hardware Architect, Electrosonic Ltd
"A great insight into a subject that has not been addressed by others - My future designs will benefit from the knowledge gained."
Harminder Bejawn, Principal Design Engineer, Thales Communications
"Management should attend this course to understand the importance of Signal Integrity for current & future products."
Andreas Gravinghoff, Hardware Engineer, ETAS GmbH

About the Lecturer

Dr. Howard Johnson,
Signal Consulting Inc.

Dr Johnson has taught thousands of students at companies all over the world, including: 3Com Corp.; IBM; Allied-Signal; Intel; Bay Networks; Mentor Graphics; Cisco Systems; Motorola; Compaq Computer; NASA; Network Equipment Technologies; Level One Communications; Siemens; DEC; Northern Telecom; Dell Computer; Sandia Nat'l Labs; Ericsson Telecom; Sun Microsystems; GEC Marconi; Texas Instruments; Hewlett-Packard; VLSI Technology.