Chapter4 SignalConnections
©NationalInstruments Corporation 4-17 6023E/6024E/6025EUser Manual
Single-Ended Connection Considerations
Asingle-ended connection is one in which the device analog i nput signal is
referenced to a ground that it can share with other input signals. The input
signalis tied to the positive input of the PGIA, and the groun dis t ied to the
negative input of the PGIA.
When everychannel is configured for single-ended input, up to 16 analog
inputchannels areavailable.
Youcan use single-ended input connections for any input signal that meets
the followingconditi ons:
•The inputsignal is high level (greater than 1 V).
•Theleads connecting the signal to the device are less than 10 ft (3 m).
•The input signal can share a common reference point with other
signals.
DIFFinput connections are recommendedfor greater signal integrity for
anyinput signal that does not m eetthe preced ing conditions.
Usingyour software, you can configure the channels for two different types
ofsingle-ended connections—RSE configuration and NRSE configuration.
TheRSE configuration is used for flo ating signal sources; in this case, the
deviceprovides the reference ground po int for the external signal. The
NRSEinput configuration is used for ground-referenced signal sources; in
thiscase, the external signal supplies its own reference ground point and the
deviceshould not supply on e.
In single-ended configurations,more e lectrostatic and magnetic noise
couples into the signal connections than in DIFF configurations. The
coupling is the result of differencesin the signal path .Magnet ic coupling
is proportional to the area between the two signal conductors. Electrical
coupling is a function of howmuch the electric fielddiffers between the
twocondu ctors.