Author Topic: Quickly Triggering Sensors - need an oscilloscope? what specs? (AU)  (Read 642 times)

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Offline nate_sydTopic starter

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I have a basic understanding of the fundamentals - but this sort of "specialty" equipment is a little beyond me.

I have 2 sensors that I need to trigger, possibly on the second rising edge (if its too hard I can do falling edge).

The process I need to do:
  • Both sensors are held high @ 4.7v (ish)
  • The first sensor transitions low for 16 microseconds
  • The first sensor goes high @4.7v - Trigger event
  • Delay of 170 microseconds
  • Second sensor goes low for 16 microseconds
  • second sensor goes high @4.7v
(Its possible I could switch to 3.3v logic, but i'd rather test at 5v if its not too much uplift)

I'd like to be able to vary the 16 microseconds by 1/10th of a microsecond.
I'd like to be able to vary the 170 microseconds by 1/10th or even 1/50th? of a microsecond.

I just need to trigger each of the sensors with the times stated a few times.
Timing is critical - from my perspective, but this could be a walk in the park for "a low budget 10mhz oscilloscope"... i'm not sure.
Can this be done with an oscilloscope?
What would the specs required be?
If its pushing the limits of a 1mhz - then i'm assuming it would be better to go to 10mhz?

Is this a basic 2 channel scope?
any special functions/features required?

Looking for a good budget model, I wont go near non-branded rubbish that could be unreliable & inconsistent.
Something like a Hantek DSO2D15 looks to be ok for $350? (amazon)
If i could get a Rigol for an extra $50-100 then I would - but they look to be a lot more

Many thanks
 

Online Ian.M

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Re: Quickly Triggering Sensors - need an oscilloscope? what specs? (AU)
« Reply #1 on: April 28, 2024, 01:06:17 am »
Oscilloscopes are for displaying signal waveforms, not creating them. 
 

Offline DimitriP

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Re: Quickly Triggering Sensors - need an oscilloscope? what specs? (AU)
« Reply #2 on: April 28, 2024, 01:28:24 am »
Oscilloscopes are for displaying signal waveforms, not creating them.

At least add that this is a job for a pulse generator or a fancy function generator and save me some typing :)   
https://www.edn.com/create-short-pulses-with-a-function-generator/
   If three 100  Ohm resistors are connected in parallel, and in series with a 200 Ohm resistor, how many resistors do you have? 
 

Offline xvr

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Offline Terry Bites

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Re: Quickly Triggering Sensors - need an oscilloscope? what specs? (AU)
« Reply #4 on: April 28, 2024, 12:17:04 pm »
A cheap as chips solution:
Use an arduino to generate the pulse pattern www.arduino.cc/reference/en/libraries/pulsepattern   github.com/RobTillaart/PulsePattern

A picture is worth a thousand words.
Here's my interpretation of your description. 2149138-0

 

Online Aldo22

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Re: Quickly Triggering Sensors - need an oscilloscope? what specs? (AU)
« Reply #5 on: April 28, 2024, 12:37:06 pm »
Oscilloscopes are for displaying signal waveforms, not creating them.

Basically yes, but the Hantek mentioned has a built-in signal generator (AWG).
This can be used to generate pulses, but not patterns (except perhaps within limits with an arbitrary waveform).

I don't quite understand the question and am therefore not sure whether he needs an oscilloscope at all.

The solution with the Arduino seems plausible.
 
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Offline nate_sydTopic starter

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Re: Quickly Triggering Sensors - need an oscilloscope? what specs? (AU)
« Reply #6 on: April 28, 2024, 09:22:29 pm »
You need Pattern Generator. https://en.wikipedia.org/wiki/Digital_pattern_generator
https://digilent.com/reference/test-and-measurement/guides/waveforms-pattern-generator
Digilent Analog Discovery 3 -  https://digilent.com/reference/test-and-measurement/analog-discovery-3/start

This was REALLY helpful - much appreciated!
Might grab the Disco2, significantly cheaper & good enough for my use case
 

Offline xvr

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Re: Quickly Triggering Sensors - need an oscilloscope? what specs? (AU)
« Reply #7 on: April 29, 2024, 09:06:25 am »
Sure, if you can find one - it's obsolete by Discovery 3
 


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