O-Scope Trigger on Glitch?

[SyncTronX]

This issue has come up again and I don't know the answer.

I was told that only an analog oscilloscope can trigger on a glitch.
and show the wave form or problem.

For some reason digital scopes are unable to capture or trigger
on a glitch. Is this true, not true, or was true 25 years ago but
no longer true?

Cheers,

 

[pelmazo]

Depends on scope.

You can't say that in general. Trigger systems are too different between scopes. Some digital scopes have better triggering capabilities than the best analog ones, including catching glitches.

If you have a digital scope with 10 Gs/s or so, their ability to see a glitch may well be superior to even a fast analog scope. Plus, they will show you the snapshot of where it happened, including some time before it happened. Ask that of an analog scope.

 

[rayma]

I was told that only and analog oscilloscope can trigger on a glitch.
and show the wave form or problem.

Turn off averaging, and instead use single shot triggering, and it should work fine.

 

[SyncTronX]

@Rayma, for analog or a digital scope?

@Pelmazo, can you give me a brand name/model or two of scopes that can do this please?

Thanks

 

[nigelwright7557]

The beauty of a digital scope is it can store pre-trigger data so you can see just before the glitch as well.

 

[rayma]

@Rayma, for analog or a digital scope?

Analog can on some events (but not all), with careful trigger setup, but a digital scope with enough memory
allows you to scroll through many individual cycles of a repetitive waveform.
http://www.hit.bme.hu/~papay/edu/Lab/MegaZoom.pdf

 

[SyncTronX]

@nigelwright7557, that is what I thought.

@rayma, yes good info also. I also found additional information from the
Agilent InfiniVision 2000 and 3000 X-Series Oscilloscopes.
Oscilloscope Selection Tip6: Triggering. Part 6 of a 12-part series.

Agilent: LINK
LeCroy: LINK
Tek: LINK

I think I've found the right information finally.

I didn't know if there were instances when there is
only a one off event of the glitch before the trigger
can capture it.

I guess that is not so today with the good digital and logging
scopes we have.

I don't have the experience to know the time frame when digital
scopes could capture the information better then the analog scopes.

If we were to ball park those years?
http://teledynelecroy.com/doc/glitch-hunting-techniques

 

[rayma]

I don't have the experience to know the time frame when digital scopes could capture
the information better then the analog scopes. If we were to ball park those years?

Some (quite expensive) digital scopes in the 90s could capture glitches well.
It's more for what cost, than when they could.