The pulse detector operates on samples. In the Perception software, this is
translated into time.
A
A
B
B
W
W
P
P
1
2
P
P
3
4
Figure 10.11:
Pulse detect/reject methods
A
Trigger
B
Width
Figure 10.11: In Diagrams
1
and
2
, the pulse detection is depicted. In Diagram
1
, when the trigger level is crossed, the signal remains above the trigger level
for a time interval larger than pulse width
W
. In Diagram
2
, there is a situation
in which the signal returns through the trigger level within pulse width
W
. A
trigger is generated on a “small” pulse.
In Diagrams
3
and
4
, the opposite situation is depicted, pulse reject. Now “small”
pulses are not recognized as trigger condition, while a wider pulse generates
a trigger.
The pulse detector can be used for both trigger levels. Combined with a
hysteresis setting, the pulse detector is less sensitive to noise on the signal.
10.4.3
Hold off
The trigger hold off feature is used to disable the trigger detector for a period
of time after a trigger condition has been met.
This can be used to generate only one trigger on a slowly decaying repetitive
signal, or to eliminate the effect of after
-
ringing. Using a 16 bit counter, triggering
can be disabled for as long as 6.5535 seconds when sampling at 10 kS/s.
GEN3i
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I3763-3.1 en HBM: public