Chapter 11
Triggering
©
National Instruments Corporation
11-5
For the trigger to assert, the signal must first be below the low
threshold, then go above the high threshold. The trigger stays
asserted until the signal returns below the low threshold. The
output of the trigger detection circuitry is the internal Analog
Comparison Event signal, as shown in Figure 11-5.
Figure 11-5.
Analog Edge Triggering with Hysteresis Rising Slope Example
–
Analog Edge Trigger with Hysteresis (Falling Slope)—When
using hysteresis with a falling slope, you specify a trigger level
and amount of hysteresis. The low threshold is the trigger level;
the high threshold is the trigger level plus the hysteresis.
For the trigger to assert, the signal must first be above the high
threshold, then go below the low threshold. The trigger stays
asserted until the signal returns above the high threshold. The
output of the trigger detection circuitry is the internal Analog
Comparison Event signal, as shown in Figure 11-6.
Figure 11-6.
Analog Edge Triggering with Hysteresis Falling Slope Example
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