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When a Signal Hits The End of a PCB Track – What happens? | Reflections by Eric Bogatin

Ringing caused by reflections can be fixed. What is happening and what to do? Explained by Eric Bogatin. Thank you Eric.
  • 00:00Understanding reflections
  • 01:06Electrically Short vs. Long
  • 02:52The tool we are using explained
  • 03:48Simulating: Electrically short
  • 08:04Reflections on classic CMOS and standard board
  • 10:41Simulating: Electrically long (e.g. DDR3 / DDR4)
  • 15:1650 OHM impedance is not 50 OHM resistance
  • 16:39Simulating a buffer example
  • 18:32Why we get reflections
  • 20:37What happens when there is a reflection
  • 25:44Why reflection disappears
  • 30:08Frequency of ringing
  • 31:49How to eliminate reflections
  • 35:37Signal level change caused by termination
  • 39:25Source termination