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See more time, See more details, Always fast, always on – Atec Agilent-5000 Series User Manual

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Why does deep memory matter?

See more time

Seeing more time is the most easily

understood use of deep memory. The

more samples you acquire, the more

time you can see at a particular sample

rate.

Long capture times give you better

visibility into cause-effect relationships

in your design, which greatly simplifies

root-cause debugging. It also allows

you to capture start-up events (like

the start-up sequence in Figure 1) in a

single acquisition.

You don’t have to stitch together

multiple acquisitions or set precise

triggering conditions. Spend less

time finding events, and more time

analyzing them.

See more details

The relationship between memory

depth and acquisition rate isn’t as

obvious. All scopes have a “banner”

maximum sample rate specification,

but many can only sustain these rates

at a few timebase settings.

In the case of an oscilloscope with a

5 GSa/s acquisition rate and 10-Kpts of

memory (Figure 2), those 10,000 points

can only fill 2 μs of time. Since scopes

have 10 time divisions, the sample rate

drops at any time/div setting below

200 ns/div.

As a result, if you look at “slow/fast”

events like a modulated signal, you

run the risk of aliasing your signal. Or

you may simply miss out on important

signal details when you zoom in on it.

Deep memory oscilloscopes let you

sustain a high sample rate over longer

periods of time.

Always fast, always on

MegaZoom III is the third generation of

the fast and deep memory architecture

that Agilent introduced in 1996. It’s

not a special mode, unlike other deep-

memory oscilloscopes. You have access

to your MegaZoom memory at all times.

And the display will respond instantly

to your commands as you scale the

+/div setting or pan and zoom in the

Delayed (or “zoom”) window.

5 GSa/s, 10k memory

4 GSa/s, 1M memory

Inflection occurs at

200 ns/div

Inflection occurs at

10 µs/div (20 s with single-shot trigger)

Sample Rate

10 GSa/s

1 kSa/s

1 GSa/s

100 MSa/s

10 MSa/s

1 MSa/s

100 kSa/s

10 kSa/s

Time Base

1

ns/div

10

ns/div

100

ns/div

1

µ

s/div

10

µ

s/div

100

µ

s/div

1

ms/div

10

ms/div

100

ms/div

1

s/div

Figure 2.

Figure 1.