Solution
The difference between analog and digital triggers is the difference in trigger source. A digital trigger is a TTL signal that is used as the starting point for the acquisition on either the rising or falling edge. The following figure shows the falling edge trigger.
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Figure 1. Digital Trigger
In contrast, an analog trigger can trigger an acquisition using a variety of methods, such as a rising and falling analog edge, an analog window, a hysteresis rising and falling analog edge.
For analog edge triggering, trigger with a specific signal level and slope. It is used to set the device to find a specific signal level and slope (rise or fall). The following figure, the trigger is set to acquire data from the rising edge signal when the signal reaches 3.2V.
![](/servlet/rtaImage?eid=ka03q000000t7Vk&feoid=00N0Z00000HEWRt&refid=0EM0Z000000SMWW)
Figure 2. Analog edge trigger
For hysteresis analog edge triggering, It is often used to reduce false triggering in signals caused by noise or jitter. When hysteresis is used at a rising slope, the trigger occurs when starting under Level-Hysteresis and crossing over Level. The trigger is released when the signal passes below the Level-Hysteresis. like the Figure 3.
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Figure 3. Hysteresis with rising slope
When hysteresis is used at a falling slope, the trigger occurs when starting above Level+Hysteresis and crossing under Level. The trigger is released when the signal passes above the Level+Hysteresis. like the Figure 4.
![](/servlet/rtaImage?eid=ka03q000000t7Vk&feoid=00N0Z00000HEWRt&refid=0EM0Z000000SMXA)
Figure 4. Hysteresis with falling slope