Agilent Technologies 1670E Series, User Manual

Page: 407 / 650

407
Logic Analyzer Concepts
Transitional Mode Theory (1660E/ES/EP-series only)
Maximum transitions stored
The following example shows the case where the transitions are
occurring at a 4-ns rate:
Maximum Transitions Stored
In this case, transitions are being detected with each sample so all
samples are stored. This situation also means each sample pair
contains a transition. For example, time tag 1 (100/000) contains a
transition and is different from time tag 2 (111/011), which also
contains a transition. The difference between the sample pairs of time
tag 1 and time tag 2 will trigger the transition detector.
If this were to continue throughout the trace, the analyzer would store
a single sample for the entire 4 K of memory, or 4096 samples. Again,
subtract one for the initial sample which is not a transition for a final
total of 4095 transitions recorded. As with the 125-MHz mode, the
actual number of transitions stored will fall somewhere between 682
and 4095, depending on the frequency of transitions.