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3-15
Triggering
The following sections provide details about analog and digital triggering of the PXIe-4310
module.
Analog Edge Triggering
For analog edge triggering, configure the device to detect a certain signal level and slope, either
rising or falling. Figure 3-10 shows an example of rising edge analog triggering. The trigger
asserts when the signal starts below level and then crosses above level.
Figure 3-10.
Analog Trigger Level
Analog Edge Triggering With Hysteresis
When you add hysteresis to analog edge triggering, you add a window above or below the trigger
level. This trigger often is used to reduce false triggering due to noise or jitter in the signal. For
example, if you add a hysteresis of 1 V to the example in Figure 3-11, which uses a level of
3.2 V, the signal must start at or drop below 2.2 V to arm the trigger. The trigger asserts when
the signal rises above 3.2 V and deasserts when it falls below 2.2 V, as shown in Figure 3-11.
Figure 3-11.
Analog Edge Triggering with Hysteresis on Rising Slope
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Reference Trigger
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Reference Trigger
