Can NI 9265 simulate micro amps current?

[venkateshcompala]

Need to generate current in micro amps resolution, for example 1/2/3/4.. micro amps, is it possible? i tried it, doesnt seems to be working.

Since the micro amps is very neglible value, is the wiring causes the issue? what kind of wiring should i use for signal connection?

Datasheet says it supports 16 bit resolution, as per my understanding, card needs to support simultion w.r.to micro amps.

[Henrik_Volkers]

The 9265 has a accuracy of 24µA 😞

But Kirchof will help you: A 1Meg Ohm resistor and 1V results in a current of 1µA. 😄

Needed accuracy?

What needs to be supplied? 

You want good isolation and cables with low microphony,  the guys who hunt pA and fA use Triax cables with graphit coated central conductor.....   

Another trick is a free flowting current source with a set of matched optocouplers, where you use the photodiodes as matched current sources, and one as a feedback reference. 

A traditional supplier for such sources and cables and KB papers on that topic is Keithley ....

[Larry_Morgan]

Here are a few things to consider: 

1: The resolution of the 9265 is on the order of 314nA per LSB. But you must also consider the noise of the module is 600nA RMS as well. 

2: The output is unipolar, only going from 0mA to 20mA. Additionally it was designed to be able to achieve as close to a true 0mA output as possible. That coupled with the unipolar design, and the module having some inevitable offset accuracy, causes there to be a slight dead-zone around 0mA. What I mean is that if you try to generate 1uA directly, you may not yet be out of the dead zone of the module and you won't see any movement on the output. It might take up to the module's typical offset accuracy of 39uA before you start to see movement. Truthfully, it could be even higher than that, since we only warrant a maximum spec, not typical. 

3: While the resolution of the module is capable of sub-uA steps, the accuracy and noise of the module are not designed to be single-digit uA accurate, so if you truly need that accuracy, you would have to verify it with an external instrument. Truthfully, this module is designed to be a very high performance module for the 0-20mA current loop applications.

I hope this helps understand some of your questions

[venkateshcompala]

Good to know the accuracy of the module 9265. So i have drop trying out this module, but i am using this module for 0 to 10mA requirement that typically works for me were in i have to drive >2mA <10 mA to test the controller board.

I could able to solve this specific requirement (2 to 5 µA)  with  high resistance (20 mega ohm) with very negligible inflow voltage from test controller board circuit.

Thanks,

Venkatesh.C.S