10.2.2
Valid trigger conditions
Trigger detection is based on level crossing. A signal has to cross a specified
level to be considered a trigger condition. As a consequence, reaching the
required level is not a valid trigger condition. Since trigger detection is digital,
inter
-
sample analog values are omitted.
In the following graphs, these conditions are shown.
T
T
Trigger
Trigger
T
Trigger
Trigger level
Sample
Last sample before trigger
Trigger
T
A
B
C
Figure 10.2:
Level crossing detector
Figure 10.2 shows the basic trigger mode with a specified level (
T
) and a level
crossing in a positive direction. In Figure 10.2
(A)
, the trigger occurs on the first
sample after the level crossing. Figure 10.2
(B)
shows the situation in which a
sample equals the set level. Trigger does not occur until a sample is actually
above the required level.
Since the trigger detector requires a level crossing, no trigger occurs when a
signal is above the set level when recording starts. This is depicted in
Figure 10.2
(C)
.
GEN3t
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I3995-3.1 en HBM: public
