buying a new DAQ

[Hasone]

My lab is looking for some good data acquisition for an experiment, and I'm finding the array of options bewildering. I never was much for shopping 🙂 If you don't mind, I'll just lay out what I'm looking for and maybe someone can help.

My lab is building an x-ray detector.  We're trying to test it, that is,  hook it up to an x-ray sample and measure it with a SQUID or equally complicated device.   We need to continuously monitor the output and send the data to the computer when we get a pulse.

 My boss envisions some sort of data acquisiton device plugging along, monitoring the sample continuously at intervals on the order of microseconds.  When there's a pulse from the detector,  he plans to have a third device (the detector itself, maybe?) send a digital signal to the DAQ to be used for triggering.  The system's fairly complex, but it might be sufficient to have the DAQ trigger itself on a rising voltage, so I think we need that. In any case, when a rising voltage is detected, the DAQ actually has to take some data. We need a baseline, so it'll have to have a buffer that is included in the data it sends off to the computer.  We expect pulses at random intervals, but at approximately 3-4 times a second.  The DAQ will have to pretty much all the work itself, because the computer won't be able to work at those speeds. Basically, I need to be able to assume no intervention from the computer until the data acquisition is complete.

So, I need a DAQ that can acquire at intervals of 1-100 microseconds and has at least a 14-bit resolution. It needs to play well with triggering and have a decent buffer. Finally, it has to be very programmable and almost-independent of the computer.  I think this is a fairly common set of requirements, but, like I said, I'm bad at shopping.

Sincerely,
Jason

jason@physics.miami.edu



On a slightly related note- I'm currently running LabWindows 6, which has no built-in support for DAQmx. Will I need to upgrade that too? Is it possible to get DAQmx to play with earlier versions of LabWindows?

[Ryan_V[DE]]

Jason,

It sounds like our M Series devices may work best for you. They offer up to 1.25MS/s sampling and 18 bits of accuracy. Depending on the duration of each acquisition, they can certainly handle several software-initiated, hardware-triggered and timed acquisitons each second. This sould require fairly minimal load on your computer. Our M Series also have a large analog input buffer, and extensive timing and triggering options. Please let me know if you would like more details.

Hope this helps,