National Instruments AT E Series - Manual (Page 73)

Chapter 4 Connecting Signals
AT E Series User Manual 4-26 ni.com
Figure 4-9 shows how to connect a grounded signal source to an
AT E Series device channel configured for NRSE mode.
Figure 4-9. Single-Ended Input Connections for Ground-Referenced Signal
Common-Mode Signal Rejection Considerations
Figures 4-6 and 4-9 show connections for signal sources that are already
referenced to some ground point with respect to the AT E Series device.
In these cases, the PGIA can reject any voltage caused by ground potential
differences between the signal source and the device. In addition, with
differential input connections, the PGIA can reject common-mode noise
pickup in the leads connecting the signal sources to the device. The PGIA
can reject common-mode signals as long as V
in
+ and V
in
– are both within
±11 V of AIGND. The AT-MIO-16XE-50 has the additional restriction
Selected Channel in NRSE Configuration
PGIA
Programmable
Gain
Instrumentation
Amplifier
+
+
–
–
+
–
Input Multiplexers
AISENSE
AIGND
V
cm
+
–
V
s
ACH+
ACH–
V
m
Common-
Mode
Noise and
Ground
Potential
Ground-
Referenced
Signal
Source
Measured
Voltage
I/O Connector