Everything you need to know to understand impedance in PCB layout (and TDR). Clear and easy to understand explanation by Eric Bogatin
Chapters:
00:00 What is this video about
00:49 What TDR is and what it does?
02:37 What is characteristic impedance
04:48 Why reflections are bad
10:54 Why do we use 50 ohm in pcb tracks?
15:28 Are lower impedance tracks more immune to noise?
23:45 Can you use any impedance for differential pairs?
27:10 What is difference between closely and loosely coupled diff impedance
36:03 Experimenting with TDR simulation
48:58 Measuring and explaining TDR on a simple pcb track
56:39 Can we do TDR on a real board?
1:02:13 Measuring and explaining TDR on a pcb track with different width
1:05:53 Answer: Why we sometimes remove ground under pads
1:07:49 Measuring a coaxial cable with TDR
1:14:51 Why you may need TDR are where it is used
1:19:00 Do we really need to care about small changes in impedance? When?
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