Chapter 2
Using the Module
2-32
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When using hysteresis with a falling slope, the trigger is armed when the signal starts above
Level
plus the hysteresis value and asserts when the signal crosses below
Level
. For example,
if you add a hysteresis of 1 mV/V to a level of 3.2 mV/V, the signal must start at or rise above
4.2 mV/V to arm the trigger. The analog comparison becomes true as the signal falls below
3.2 mV/V and becomes false when it rises above 4.2 mV/V, as shown in Figure 2-22.
Figure 2-22.
Analog Edge Triggering with Hysteresis on Falling Slope
Window Triggering
A window trigger occurs when an analog signal either passes into (enters) or passes out of
(leaves) a window defined by two levels. Specify the levels by setting a value for the top and
bottom window boundaries. Figure 2-23 demonstrates a trigger that acquires data when the
signal enters the window. You can also program the trigger circuit to acquire data when the
signal leaves the window.
Figure 2-23.
Window Triggering
Level
Analog Comparison
Hysteresis
4.2 mV/V
3.2 mV/V
Reference Trigger
Window Top
Window Bottom
Analog Comparison
Reference Trigger
