Product data

Why does a fast update rate matter?
While bandwidth, sample rate and memory depth are key criteria for deciding
which scope to purchase, an equally important characteristic is update rate.
What is update rate?
Update rate is how many waveforms acquisitions per seconds you scope can
acquire, process, and display.
Oscilloscope “dead-time” is the time it takes for
a scope to process and then display an acquired waveform before re-arming
it’s triggering for the next acquisition. For traditional scopes, this time is often
orders of magnitude greater than acquisition time on fast time-per-division
settings.
If a glitch occurs during the scope’s dead-time, it won’t be captured. The key
to improving the probability of capturing a signal anomaly during the scope
acquisition time is to minimize dead-time.
Oscilloscope vendors usually specify what their scope’s “best-case” wave-
form update rates are. Some scope architectures suffer from factors that can
seriously degrade the “best-case” update rates spec.
Agilent’s 7000 Series
architecture delivers the world’s fastest update rate when using:
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Analog channels
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Analog and digital
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Deep memory
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Serial decode
Why is update rate important?
Responsiveness. If you rotate the timebase control, you expect the
oscilloscope to respond immediately – not seconds later after the scope
fi nishes processing data.
Signal detail. Fast waveform update rates improve the display
quality of the waveform that you see on screen.
Certainty. Fast waveform update rates improve the scope’s probability
of capturing random and infrequent events.
Update rates directly affect a scope probability of capturing and displaying
infrequent and random events. Slow update rates will cause a scope to miss
subtle or infrequent signal details.
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Improves instrument responsiveness
Improves scope display quality
Improves probability of capturing
infrequent events
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