User`s guide

7
Why does a fast update rate matter?
This is a question that we hear
frequently. If the human eye has
trouble discerning above 30-50
frames per second, is there really a
difference between 3,600 and 100,000
waveforms per second? If you know
what you’re looking for the answer
is probably “no”. However, if you are
hunting for unknown signal anomalies
or characterizing jitter, the answer
is “yes”.
Acquisition
time
Dead
time
Dead
time
Acquisition
time
Reducing the dead time between
acquisitions …
… improves your chances of finding
random events like glitches.
1.0E-09
1.0E-08
1.0E-07
1.0E-06
1.0E-05
100000
10000
1000
100
10
1
Waveforms per second
Time base setting
Agilent MSO6054A, 8 Mpts optional
Tek MSO4054A, 10 Mpts
LeCroy WaveRunner Xi 104Xi, 12.5 Mpts
Comparison of waveform update rates using each scope’s default real-time acquisition
mode, digital channels and maximum memory.
Catch problems sooner and cover more of your debug checklist – our 100,000
waveform per second update rate helps you find intermittent problems faster
than comparable scopes.
If you know that there is a glitch in
your system, it’s easy to capture it
using a pulse-width trigger. However,
if you are just browsing through your
design, your chances of finding a glitch
increase as the update rate increases.
If a glitch occurs during the “dead
time” between sample, you miss it.
With MegaZoom III technology, the
dead time is much smaller. A scope
with a slower update rate will capture
the glitch eventually (if it recurs), but
most engineers and technicians don’t
have the time or patience to wait for
their tools to catch up.
If you are characterizing signal jitter,
a fast update rate gives you accurate
results sooner. And when the fast
update rate is combined with the 6000
Series’ XGA high-definition display
(1024 x 768, 256 intensity levels),
subtle differences in these acquisitions
become obvious.
The Agilent 6000 series fast update
rate is truly uncompromised. Even if
digital channels are turned on, or serial
decode is being utilized the update
rate remains constant at 100,000
waveforms/sec and the full memory
depth of up to 8 Mpts is always
available to you.
And like all other aspects of
MegaZoom III technology, this is
a real-time acquisition mode. It’s
always fast, always on.
Learn more about the benefits
of a fast update rate by reading
Application Note 1551 - Improve Your
Ability to Capture Elusive Events: Why
Oscilloscope Waveform Update Rates
are Important.