imageI’ve been teaching signal integrity for more than 20 years and keep getting asked the same questions over and over again. That’s one reason I wrote my text book, Signal and Power Integrity- Simplified.

I read so many on-line forums where engineers- both novices and very experienced, ask some very important fundamental questions, and the responders struggle or muddle through the answers.

I tried to include the answers to many of these questions in my book. Here is a short list of 20 questions which are answered in detail in my text book. If you puzzle over some of these signal integrity questions, you might find it instructive to browse through my text book.

 

 

  1. Why are signal integrity problems only going to get worse as we progress on Moore’s Law? (section 1.7)
  2. Why is the bandwidth of a signal related to 0.35/RT? (section 2.10)
  3. What is the origin of the rule of thumb that the bandwidth of a clock signal is roughly the 5th harmonic of the clock frequency? What are the underlying assumptions? (section 2.13)
  4. What is the difference between a “real” component and an “ideal” circuit element and why is this distinction important? (section 3.3)
  5. What is sheet resistance and why is this an incredibly useful figure of merit? (section 4.5)
  6. Why is the capacitance of a simple, short wire hanging in space about 2 pF? (section 5.2)
  7. What really is inductance and how is it influenced by physical design? (section 6.3)
  8. What is ground bounce and how can I reduce it? (section 6.7)
  9. Why does current in a conductor re-distribute at high frequency? (section 6.16)
  10. What does characteristic impedance really mean? (section 7.9)
  11. How does return current really flow in a transmission line? (section 7.13)
  12. How does return current flow from one plane to another when the signal transitions through a via? (section 7.14)
  13. Why are there reflections? (section 8.2)
  14. Do corners cause reflections and when should I care? (section 8.16)
  15. Where does dissipation factor and dielectric loss come from? (section 9.6)
  16. Why are the capacitance matrix elements sometimes negative? (section 10.6)
  17. What is differential impedance and how is it different from odd mode impedance? (section 11.7)
  18. Why is there no far end cross talk in stripline? (section 11.11)
  19. Why are there always ripples in return loss and sometimes in insertion loss? (12.11)
  20. What is spreading inductance and why is this important? (section 13.14)