Sinking current into PXI 6723

[BLowery]

I need to replace a potentiometer in a voltage divider with an AO channel on the PXI 6723 (as seen in the attached child-like drawing).  I'm not a circuits whiz, but I believe I'll be sinking current into the card whenever the voltage is below 5V (a KVL loop says about 9.6mA at my minimum expected voltage of 0.2V).  In the 6722/6723 spec sheet, it has a column labeled "Sink" and says the AO channels can handle 5mA at -10V.  Are these two numbers given so I can calculate the power-sinking capabilities of the card?  So I'm safe as long as any combination of voltage/current I give it stays below that wattage?  

Thanks, in advance, for any help you all can toss my way!

[caro16av]

Hi Blowery,

So this is the Spec sheet for the NI 6723:

http://www.ni.com/pdf/manuals/370822c.pdf

In the Voltage output section you can see that the device is able to output a max of ±5 mA, about the sinking current I did not find the Chart that you specify.

About your question,  those numbers are not meant for you to calculate the power sinking capabilities, they express the maximim, and you should not increase the current even if you lower the voltage. You are not safe just by keeping the wattage in range, you need to keep below the currents limits.

In the specs sheet you can see the max currents you might input in the Digital I/O:

Input low current (Vin = 0 V)  320 μA 

Input high current (Vin = 5 V) 10 μA

The device was not design to sink current, so I do not recommend to set the AO in that situation.

Regards,

Carolina