Three Formats
Advanced High-Speed Signal Propagation
For
Experienced Digital Designers, by
Dr. Howard Johnson
This is an advanced-level 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 two-day course teaches a unified theory of transmission impairments that apply to any transmission media. This course is an advanced sequel to High-Speed Digital Design.
Main Topics
| Skin effect | Lossy media |
| Dielectric loss | Single-ended and differential signaling |
| On-silicon transmission-line behavior | Frequency-domain modeling |
| Equalization | Signal distribution |
| Serial interconnections | Signal transition regions |
Course Syllabus
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 and frequency
- Introduce rules of scaling related to the physical extent of a circuit
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
Performance regions: on-silicon vs. off-chip
- Present the standard copper performance model
- Explore the hierarchy of transmission-line performance regions
- Classroom demonstration: A transmission line is always a transmission line
- 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
- Example waveforms: 10 Gb/s serial link with PAM-4 coding and fully adaptive equalizer
S-parameter theory and application
- Why bother with frequency-domain characterization?
- Advantage of linear-time-invariant modeling
- S-parameter test setup
- Using S-parameters
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 movie: 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 clocks
- Show why serpentine delays often deliver poor results
- Present strategies for driving multiple loads from one source
- 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
Who should attend?
- Digital logic designers
- System architects
- Chip designers
- EMC specialists
- Applications engineers
- Anyone who works with digital logic at speeds in excess of 1GHz
This is a practical course. It is filled with practical examples and explanations. A basic understanding of the frequency domain representation of linear systems is assumed. Delegates without the benefit of formal training in analog circuit theory can use and apply the formulas and examples from this course. Delegates who have completed (at least) a first-year class in introductory linear circuit theory will comprehend the material at a deeper level.
Who Has Participated
Dr. Johnson has taught thousands of students at companies all over the world, including:
| Who Has Participated | ||
|---|---|---|
| Agilent | Honeywell | Nokia |
| AMD | IBM | Qualcomm |
| Boeing | Intel | Rockwell-Collins |
| Cisco Systems | L-3 Comm. | Rohde & Schwarz |
| Dell Computer | Lockheed Martin | Samsung |
| Ericsson | Mentor Graphics | Sandia National Labs |
| General Dynamics | Microsoft | Tektronix |
| Harris Corp. | Motorola | Texas Instruments |
| Hewlett-Packard | NASA | US Naval Warfare Systems |
What People Are Saying
"Excellent real world practical information that will immediately impact my work." - Raytheon Engineer
"Cool class!. It explains all my mistakes." - Engineer, US Navy
"Management should attend this course to understand the importance of Signal Integrity for current and future products." - Hardware Engineer, ETAS GmbH
"Very practical! Real situations at exist at work. This analysis wil save us as things go faster." - Design Engineer, Hewlett Packard Laboratories