Hello, this is Guu.
This time, I summarized the questions that arose when I measured the signals of the board we produced in the training using an oscilloscope.
An oscilloscope is a device that detects changes in electrical signals over time as waveforms.
By using it, we can see electrical signals that are invisible to the eye.
It is a useful device!
One of the most useful functions of an oscilloscope is the "trigger function.
It sounds like a cool feature, but here is what happens when you use it.
When triggered, the multiple overlapping waveforms are reduced to a single waveform.
By doing so, the rising and falling edges of the waveform can be checked.
Now that we know that triggering is useful, why does it make waveforms easier to see?
What does the act of "triggering" do in the first place?
Such questions come to mind.
Explanation
When you look at an oscilloscope screen, the vertical axis shows "voltage" and the horizontal axis shows "time".
When using the trigger function, "trigger level" and "trigger position" are displayed as shown in the figure below.
The trigger level indicates "voltage" and the trigger position indicates "where the waveform is displayed.
Triggering" is the act of taking out only the waveforms that pass through the "set voltage (threshold)" at the trigger level.
By continuing to display only the triggered waveforms, the waveforms appear to stop.
In other words, it is like setting a trap in a certain place under certain conditions.
Only when the trap (trigger) is caught, the prey (waveform) can be obtained.
Also, by setting the position of the trigger (rising edge, falling edge, etc.), you can get the waveform you want to see (or know).
Conclusion
Trigger function is a function to retrieve only the waveform passing through the point at that moment by setting the location (trigger position) and voltage (trigger level).
By changing the measurement conditions, you can also get the waveform you want to see (or know) more.
Guu's tweet
The "trigger function" is not only a cool name, but also a very useful function.
I'll try my best to master it!
Extra
I would like to introduce another useful function of the oscilloscope.
It is the "Waveform Overlapping Function.
The length of one cycle of a waveform varies. When one cycle is 10 ns, sometimes it is 10.001 ns and sometimes it is 9.999 ns.
This variation is called "Jitter".
The "Waveform Overlapping Function" is used to see how much the Jitter is.
By overlapping the waveforms, you can clearly see the periodic discrepancy as shown in the figure below.
New Engineer's Blush Blog Article List