Hysteresis

[Heyou]

Basic Level Trigger Detection vi. Hysteresis

What is the hysteresis level? Is it a percentage a voltage level or what?

[RTSLVU]

signal in contains the signal in which to detect a trigger.

level specifies the threshold value signal in must cross before a trigger is detected. The default is 0.

hysteresis specifies the amount above or below level through which signal in must pass before a trigger level crossing is detected. The default is 0.

http://zone.ni.com/reference/en-XX/help/371361M-01/lvwave/basic_level_trigger_detect/

So basically once "Signa In" cross "level" trigger=True and it will remain True until "signal In" crosses "hysteresis".

[Heyou]

In layman's terms if I wanted to trigger at 3.00V with a negative slope and had a hysteresis of .01, I would theoretically trigger somewhere between 3.00V and 2.99?

[RTSLVU]

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@Heyou wrote:

In layman's terms if I wanted to trigger at 3.00V with a negative slope and had a hysteresis of .01, I would theoretically trigger somewhere between 3.00V and 2.99?

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Negitive slope? Do you want to trigger on -3.00 volts or triggir on the falling edge of a +3.00 volt pulse?

You will have to bear with me here as I have never used the trigger VI, but have used an ocillioscope to trigger on all sorts of crazy waveforms...

I would imagine that the trigger VI would operate the same as the triggering on a modern DSO.

[Heyou]

I have a falling voltage starting at 3.3v it crosses at 3.00. I want to trigger there.

[RTSLVU · Accepted solution]

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@Heyou wrote:

I have a falling voltage starting at 3.3v it crosses at 3.00. I want to trigger there.

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Well I would set the trigger for 3.00 volts and trigger on the falling edge to begin with and work from there.

[Heyou]

I missed the falling edge selection on the VI. That seems to have locked it in.