LeCroy SDA, Operator'S Manual

Page: 62 / 397

Because each instrument input channel has a dedicated ADC (Analog-to-Digital Converter), the
voltage on each is sampled and measured at the same instant. This allows very reliable time
measurements between the channels.
On fast timebase settings, the maximum single-shot sampling rate is used. But for slower
timebases, the sampling rate is decreased and the number of data samples maintained.
The relationship between sample rate, memory, and time can be simply defined as:
and
Sequence Sampling Mode Working With Segments
In sequence mode, the complete waveform consists of a number of fixed-size segments acquired
in single-shot mode (see the instrument specifications for the limits). Select the number of
segments to be captured, then select each segment individually and use it for processing with
math and measure tools.
Sequence mode offers a number of unique capabilities. With it, you can limit dead time between
trigger events for consecutive segments. The instrument can capture in fine detail complicated
sequences of events over large time intervals, while ignoring the uninteresting periods between
the events. You can also make time measurements between events on selected segments using
the full precision of the acquisition timebase.
Each individual segment can be zoomed or used as input to math functions.
The instrument uses the sequence timebase setting to determine the capture duration of each
segment: 10 x time/div. Along with this setting, the scope uses the desired number of segments,
maximum segment length, and total available memory to determine the actual number of samples
or segments, and time or points. However, the display of the complete waveform with all its
segments may not entirely fill the screen.
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SDA-OM-E Rev H