Genesis GEN3t, Руководство пользователя

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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.
GEN3t
146 I3995-3.1 en HBM: public