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Is there any way to calculate the stability of an instrument such as current sources and digital voltmeters from their datasheet?

Let me provide one example. My application requires stable current sources (better than 100ppm for a few hours) capable of feeding a probe with 10 mA. In principle, I could use the Keithley 6221 to do so. If I check its datasheet, I find this:

enter image description here

For 10 mA, the accuracy would be +/-(0.05% * 10 mA + 10 uA) = +/-15 uA (1500 ppm with regard to 10 mA). Of course this is accuracy and not stability. But then, with the information above, how could I tell whether this instrument is or is not appropriate for my 100ppm stability specs? Can I reach any conclusion just based on the typical noise? If so, how to?

Thanks, folks, Take care.

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    $\begingroup$ Is the 10mA requirement nominal or include any surge current? $\endgroup$ Nov 1 '20 at 15:04
  • $\begingroup$ It is requirement nominal. It does not include the surge current. $\endgroup$
    – jeb
    Nov 2 '20 at 13:08
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I suggest that you take a closer look at typical noise. I have highlight the area of the specification for you reference. The best method is to confirm is measure the output to confirm the output.

enter image description here

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  • $\begingroup$ I see. But let's suppose that among several options to buy, I would like to purchase an instrument based on what the datasheet guarantees. In this example, how do you interpret the RMS information? What does it mean to have 0.4 uA for a band between 0.1 and 10 Hz? $\endgroup$
    – jeb
    Nov 2 '20 at 13:07

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