Rodeostat Specs

  • Hi,

    I'm thinking about using Rodeostat for my project, but I'm not sure if it will fit.
    We need to read:

    • Maximum Currents of 200uA; (from the page, the Rodeostat can read up to 1uA, correct?)
    • Current ranges of 10nA to 200 uA;

    Is it possible? How's the Potential Accuracy and Precision? How's the Current resolution?
    If not, could it be modified to cover those specs?


  • @rcbb

    The Rodeostat has four user selectable current ranges: -1uA to +1uA, -10uA to +10uA, -100uA to +100uA and -1000uA to +1000 uA. When in a given current range it can measure currents between those two (minimum and maximum) values. So for example in the -10uA to 10uA current range it can measure currents between -10uA and 10uA.

    The analog input used to sample the current values (after the transimpedance amplifier) has a usable resolution of 13 bits - so there are 2^13 = 8192 possible values for the current measurement. The minimum possible resolution for a given current range is given by the full scale range divided by the number possible values. So for the -1uA to +1uA the minimum possible resolution would be 2uA/8192 = 0.24nA. Similarly the -10uA to +10uA, -100uA to +100uA, and -1000uA to +1000uA current ranges would have a minimum possible resolutions of 2.4nA, 24nA and 240nA respectively. In practice noise on your measurements could increase these values somewhat from the minimum possible values. The details would depend on your specific experimental setup.

    In short I think the Rodeostat will work for what you want to do - at least in terms of current range.


  • Thanks, Will. That elucidates a lot!
    We are concerned with the noise, but we'll have to try it first.
    I'll buy one for test and see how it goes.

    Thanks again.

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