Tektronix TDS2000C series User manual

Troubleshooting Your Design
with the TDS2000C Series Oscilloscopes

Troubleshooting Your Design with the TDS2000C Series Oscilloscope .................... 4
Getting Started ....................................................................................................... 5
Capture Elusive Glitches and Anomalies .............................................................. 6-7
Debug Digital Timing Problems ............................................................................... 8
Verify Timing Relationships ..................................................................................... 9
Check Signal Integrity ...................................................................................... 10-11
Debugging Digital System Lock-up ....................................................................... 12
Test for Presence of Video Signals ........................................................................ 13
Look for Unintentional Circuit Noise ................................................................. 14-15
Power Line Harmonic Analysis ......................................................................... 16-17
Automatically Capture and Save Elusive Waveform Anomalies .............................. 18
Make a Quick Pass/Fail Test of Your Device .......................................................... 19
Documenting Your Results with OpenChoice® Software ....................................... 20
Waveform Measurements Logging ....................................................................... 21
Waveform Analysis using NI SignalExpress™ Tektronix Edition ............................... 22
Table of Contents

TDS2000C Series Oscilloscope www.tektronix.com/tds2000 4
Today’s engineers and technicians face increasingly complex and
critical troubleshooting tasks. New digital designs often challenge
designers with new problems to find: race conditions, transients,
signal aberrations, bus contention problems, etc. And, of course,
competitive time-to-market pressures dictate that troubleshooting
must be completed quickly and accurately.
The TDS2000C Series delivers the performance, affordability and
portability that enable engineers and technicians to tackle these
challenges – quickly and easily. More than just a matter of basic
bandwidth, these oscilloscopes enable users to solve problems
quickly, helping them to establish that a problem exists, allowing
them to capture the problem accurately, and enabling them to
analyze it to determine the root cause.
Troubleshooting Your Design with the TDS2000C Series Oscilloscope
The tips on the following pages are designed to further simplify
your troubleshooting tasks. But if you need more help, there is
plenty available. Simply contact your local Tektronix representative,
authorized distributor, or visit www.tektronix.com/oscilloscopes
50, 70, 100, and 200 MHz models
Up to 2 GS/s sample rate on all channels
Active TFT Color Display for easy viewing at a distance, at an
angle, or under dim lighting conditions
Built-in USB host and device ports standard
Easy documentation and analysis with PC connectivity software
Lifetime warranty*
* Limitations apply. For terms and conditions, visit
www.tektronix.com/lifetimewarranty

TDS2000C Series Oscilloscope www.tektronix.com/tds2000 5
Getting Started
To optimize your troubleshooting task at hand, it is important to start
at the beginning – with proper probe compensation and attenuation,
default setup, and automatic instrument setup.
To properly compensate and attenuate your probe,
follow these simple steps:
1. Connect the probe to channel 1.
2. Attach the probe tip and reference lead to the PROBE COMP
connectors. If using the probe hook-tip, ensure a proper
connection by firmly twisting the tip onto the probe.
3. Push PROBE CHECK.
4. The oscilloscope will automatically check the probe attenuation
and check the shape of the displayed waveform to determine if
your probe is compensated correctly.
5. If necessary, it will instruct you to adjust your probe compensation.
To ensure that you begin with factory initialization
settings, follow these simple steps:
1. Press the front panel DEFAULT SETUP button.
2. Press the front panel AUTOSET button.
PROBE COMP AUTOSET
button
CH 1
Overcompensated
Undercompensated
Compensated Correctly
TPP Series

TDS2000C Series Oscilloscope www.tektronix.com/tds2000 6
Capture Elusive Glitches
In today’s high-speed digital designs, elusive glitches and random
anomalies can cause circuits to fail. While finding these glitches has
never been easy, the TDS2000C Series simplifies this task with its
peak detect feature. Peak detect can capture narrow glitches, even
on low-frequency signals.
To use the Peak Detect feature:
1. Display the waveform on the screen.
2. Press the ACQUIRE front panel menu button.
3. Press the Peak Detect menu button.
4. Notice that the oscilloscope captures several very narrow glitches,
even at slow sweep speeds. Without peak detect, you would not
have seen many of these glitches.

TDS2000C Series Oscilloscope www.tektronix.com/tds2000 7
Capture Elusive Glitches (continued)
Intermittent signal anomalies can also be a challenge to see. The
TDS2000C Series provides variable- and infinite-persistence display
capabilities to provide you with information about the signal
variations over time, making it easier to understand the
characteristics of the transients you’ve captured.
To use Display Persistence:
1. Display the waveform on the screen.
2. Press the DISPLAY front panel menu button.
3. Press the Persist menu button until the desired amount of
persistence is selected.
4. Notice that the most recent signal is highlighted in the display.
By monitoring the screen updates, you can judge the relative
frequency-of-occurrence of the signal anomalies.

TDS2000C Series Oscilloscope www.tektronix.com/tds2000 8
Debug Digital Timing Problems
Digital designers need to quickly find and analyze a wide range of
circuit timing problems. For example, race conditions and transients
can cause circuits to perform inaccurately. The TDS2000C Series’
pulse width trigger can help troubleshoot such situations by
triggering when a signal pulse width is less than, greater than,
equal to or not equal to a specified pulse width.
To use the pulse width trigger:
1. Press the TRIG MENU front panel button.
2. In the side menu, press Type until Pulse is selected.
3. Press the When side menu button until < is selected.
4. Use the multipurpose knob to set the desired minimum
pulse width.
5. Select, as desired, Source, Polarity, Mode, and Coupling.

TDS2000C Series Oscilloscope www.tektronix.com/tds2000 9
Verify Timing Relationships
Electronics engineers often need to verify that their circuits
are working as designed. One of the most common types of
oscilloscope measurements is timing measurements, such as pulse
width, period, and frequency. The TDS2000C Series’ cursors can be
used to make such measurements quickly and easily.
To make timing measurements using cursors:
1. Press the CURSOR button.
2. Press the Type menu button until the Time cursor type is
selected.
3. Press the Cursor 1 menu button.
4. To measure the timing relationship between two signals, place
cursor 1 on the first edge of interest, using the multipurpose knob.
5. Press the Cursor 2 button and place cursor 2 on the second
edge of interest, at approximately the same Voltage.
6. The cursor readouts indicate the timing of the cursors relative
to the trigger point. In this example, the Δt readout indicates
the period of the waveform, and the 1/Δt is the frequency of
the signal.

TDS2000C Series Oscilloscope www.tektronix.com/tds2000 10
Check Signal Integrity
Electronics engineers may discover that a wide array of unintentional
electrical events will make a difference in how circuits function in the
real world. To characterize these events, engineers can measure
criteria such as overshoot, ringing, ground bounce, cross talk, and
other signal integrity issues. The TDS2000C Series’ cursors can be
used to make such measurements.
To make signal integrity measurements
using cursors:
1. Press the CURSOR button.
2. Press the Type menu button until the Amplitude cursor type is
selected.
3. Press the Cursor 1 menu button.
4. To measure the peak ringing below ground, place cursor 1 at 0
Volts, using the multipurpose knob.
5. Press the Cursor 2 menu button and place cursor 2 on the
negative peak, using the multipurpose knob.
6. View the absolute Voltage measurements on the cursor readouts
at the side of the display. The Δ readout indicates the difference
between the cursor positions.