time domain reflectometry in PCB S-maram design for signal integrity

Thread Starter

yef smith

Joined Aug 2, 2020
Hello , We design PCB , its basicly transmission lines of two ends.
we extract S-parameters,then we ussualy connect some PULSE source to test the signal integrity using (time domain reflectometry).

time domain reflectometry is being used for to get the impedance at every point of the path in which the pulse is traveled in, i dont see what it will give us.
What is the purpose of TDR in PCB design?


Joined Dec 30, 2022
In PCB (printed circuit board) design, TDR can be used to identify and locate faults or discontinuities in transmission lines, such as open or shorted circuits, impedance mismatches, or parasitics. This can be useful for debugging and troubleshooting high-speed signaling circuits, as well as for ensuring that the transmission lines meet the desired electrical performance specifications.

TDR measurement equipment, such as oscilloscopes or specialized TDR probes, can be used to send a pulse down the transmission line and measure the time it takes for the reflection to return. The characteristics of the reflection, such as its amplitude and shape, can provide information about the nature and location of any discontinuities in the transmission line.

TDR can be an important tool in PCB design, as it can help identify and resolve issues that could affect the performance and reliability of high-speed signaling circuits.