Multifunction DAQ
WHat Sampling Rate Do I need?
What exactly do you measure? If you sample just analog signal, then you need at least 2 time measured frequency to keep frequency information from measured signal, and at least 10 times the measured frequency to keep shape information. To be more precise, I mean 2 times or 10 times the highest frequency component from the signal you want to measure. That's when we speak about analog signals.
But as I understand, you have digital signal, likely pulse train (just guess). The most important is to answer question what do you want to do with the signal. Do you want to use analog input to see shape? Or do you want to measure timing parameters of the signal?
Please give us more information on what you try to accomplish, then we can be helpful.
regards,
stefo
Rafi,
I believe that the best for you would be to use counter to measure timing parameters of your pulse. If you use some multifunction board like M or X series, then you can use pulse with measurement. With pulse with measurement you can get precise timing information, as you will count number of pulses of your timebase (can be 100MHz) which falls within measured pulse.
If you have a look into X Series User Manual, then in chapter 7 (counters) you can find Counter Input applications - list of thinks you can measure with counters 😄 You should be able to find even timing diagrams for those measurement.
regards,
stefo
Rafi,
if you don't have device yet, then take cDAQ with fast digital input module which is able to accept higher voltage. Then you can use it as couner, and it will be far more accurate timing measurement then you could ever achieve with AI on multifunction DAQ.
But, of course you can measure analog signal, get all the data and recalculate in software what is the pulse width, but I think it is overcomplicated solution.
regards,
stefo
