EE 461 Digital System Design - PowerPoint PPT Presentation

1 / 4
About This Presentation
Title:

EE 461 Digital System Design

Description:

A TDR is an oscilloscope that has a built in step generator. ... The inputs to the TDR/TDT oscilloscope are all 50ohms, so connecting the Far-End ... – PowerPoint PPT presentation

Number of Views:34
Avg rating:3.0/5.0
Slides: 5
Provided by: profbrock
Category:

less

Transcript and Presenter's Notes

Title: EE 461 Digital System Design


1
EE 461 Digital System Design
  • Lecture 34
  • Agenda
  • Lab 11 (TDR)
  • Announcements (Monday, 4/21)
  • All PCB's will be in this week.

2
Time Domain Reflectrometry
  • TDR- A TDR is an oscilloscope that has a built
    in step generator. - The instrument sends out a
    fast step and simultaneously observes the
    reflected energy.- The system built to be
    50ohms.- This means if you terminated the
    system, the TDR would observe the initial step
    then no ensuing reflections- If there were
    impedance discontinuities (i.e., from
    interconnect), then the TDR would observe the
    reflections.- By looking at the magnitude,
    duration, spatial location of the reflections,
    the source of the impedance discontinuity can
    be isolated and analyzed.

3
Time Domain Transmission
  • TDT- We can also connect the Far-End of our
    system back into another channel of the TDR
    oscilloscope- Observing the transmitted signal
    is called Time Domain Transmission (TDT)- This
    observation point gives the amount of energy that
    was successfully transmitted through the
    interconnect structure.- The inputs to the
    TDR/TDT oscilloscope are all 50ohms, so
    connecting the Far-End of the system to a TDT
    input is a convenient method to terminate the
    system.

4
TDR/TDT
  • Literature- The following Application Notes
    give some additional theory on TDR/TDT some
    practical methods to use the information.-
    These are located on the Course Website under
    "Information"
  • Time Domain Reflectrometry Theory, Agilent
    Technologies Measuring Parasitic Capacitance
    Inductance Using TDR, Agilent Technologies
    Signal Integrity Analysis using TDR, Agilent
    Technologies Time Domain Methods for Measuring
    Crosstalk for PCB Quality Verification, Tektronix
Write a Comment
User Comments (0)
About PowerShow.com