What is the difference between a TDR and a couple of function generator + scope ? Rise time is much faster on TDR devices ? No multiple interconnection reflections ? TDR can deliver much more power thus drive very long capacitive cables ?
Thank you for this instructive presentation on TDR. It is very refreshing old myths relating transmission line reflections are explained with with clear and simple examples.
A stupid question: how many reflections happened at each time position on the waveform? Only one reflection or accumulate of multi reflection? Such as there is bounce at the point of discontinue, is the bounce caused by one reflection?
No you can but maintain return path without screwed so use return vias on layer transition there is proper return path hence no impedance discontinuity
@@Bornachiever17 with a return via the signal via is like a very short microstrip without impedance control. I remember I have seen a US pattern regarding impedance controlled via.
you are correct :) there is some way to improve it however . you can add some ground vias near by for the return path , by doing so , you will minimize the change of impedance
Everbody responding is giving you good advice. Avoid layer changes if you can, and when you must, be sure you add some ground vias to compensate in the return path. You can then keep the discontinuity small and (hopefully) insignificant depending on operating frequency.
You know someone has mastered his craft when he can explain it to a beginner and the beginner understands it like a specialist... This is so great
Thank you I appreciate this.
What is the difference between a TDR and a couple of function generator + scope ? Rise time is much faster on TDR devices ? No multiple interconnection reflections ? TDR can deliver much more power thus drive very long capacitive cables ?
Thank you for this instructive presentation on TDR. It is very refreshing old myths relating transmission line reflections are explained with with clear and simple examples.
Starts at 6:20
Thank you!
This one is Part 1 of 6, where are the remaining parts?
A stupid question: how many reflections happened at each time position on the waveform? Only one reflection or accumulate of multi reflection? Such as there is bounce at the point of discontinue, is the bounce caused by one reflection?
@35:14 , you get offset less then 50ohm , less resistive , is it ?! , but in other test you get higher offset , higher resistive , is it ?
Can we get the small book online ?
this means that on PCB , changing layer by via is not good if you want uniform 50 ohm impedance , is it ?!
is it?
No you can but maintain return path without screwed so use return vias on layer transition there is proper return path hence no impedance discontinuity
@@Bornachiever17 with a return via the signal via is like a very short microstrip without impedance control. I remember I have seen a US pattern regarding impedance controlled via.
you are correct :) there is some way to improve it however . you can add some ground vias near by for the return path , by doing so , you will minimize the change of impedance
Everbody responding is giving you good advice. Avoid layer changes if you can, and when you must, be sure you add some ground vias to compensate in the return path. You can then keep the discontinuity small and (hopefully) insignificant depending on operating frequency.
Truly shows what a genius this guy is. If one of his books turns out to be full of crap he can still sell it as fiction!