From Friday, April 19th (11:00 PM CDT) through Saturday, April 20th (2:00 PM CDT), 2024, ni.com will undergo system upgrades that may result in temporary service interruption.

We appreciate your patience as we improve our online experience.

Multifunction DAQ

cancel
Showing results for 
Search instead for 
Did you mean: 

Terminate unused inputs?

My group reads/writes analog voltages using an NI PCIe-6363 board an two BNC-2110 connector blocks.  We only use about half of the AI/AO channels.  I am wondering if we should terminate the inputs of unused channels.  I am not an electronics expert, but I am aware that when working with logic circuits (e.g., TTL logic), unused inputs should be terminated by either pulling down to ground or typing up to Vcc.  Is it recommended or helpful to terminate unused inputs in some way?  I find nothing about this in available documentation.  Thank you for thinking about this with me!

0 Kudos
Message 1 of 3
(1,347 Views)

Hi smkuebler,

 

In this DAQ X user series manual:

https://www.artisantg.com/info/National_Instruments_PCIe_6323_Manual_2018115104919.pdf

NI recommends connecting unused channel inputs AI+ and AI- to AIGND. This prevents the inputs from floating outside of the Vcm rating. 

0 Kudos
Message 2 of 3
(1,306 Views)

We never followed this recommendation and never had a problem.

Who among you connects the unused inputs to the ground?

0 Kudos
Message 3 of 3
(1,294 Views)