Is the SCC-CO20 output current truly constant regardless of variable load?

I am currently trying to put together a hardware system that (among other things) will provide a train of current-controlled pulses [required amplitude range = 0 - 10 mA (but fixed at a constant level during each pulse); possible pulse duration range = 1 - 100+ ms] into an external load whose impedance might vary in magnitude during the duration of each pulse. I came across the SCC-CO20 module, whose User Guide states (page 1) "...the output current is proportional to the voltage applied to the module by an analog output channel." Unfortunately, I can't seem to find any additional info within that Guide that explicitly speaks to whether that current output is truly independent of external load variations. Does anyone know this info (and/or where I can find it)? Furthermore, if it really is independent, then would some also know where I could find specs detailing the frequency response and/or stability of the output to variable loads (that is, specs regarding the ability of the module to maintain a constant current level in the face of varying loads)? Thanks.

Hi dygarth,
The SCC-CO20 module will keep the current constant independant of the load, assuming it can source enough current for the load. The following (from the SCC-CO20 Manual) shows the maximum load you can use at each specific current output amount:
5 mA ................................................2,500 Ω
10 mA ..............................................1,250 Ω
15 mA ..............................................830 Ω
20 mA ..............................................625 Ω
We do not provide any specs detailing the frequency response for variable loads. However, converting voltage to current is in essence just a first order circiut (voltage across a resistor), which in theory doesn't add in any delay. Generating pulses in the millisecond range with the SCC-CO20 should not be a problem.
Thanks,
Justin M.
National Instruments

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***Yes, I am aware I am replying to a very old post***
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