Chapter 3
Connecting the Signals
DAQPad-MIO-16XE-50 User Manual
3-18
ni.com
Figure 3-7 shows how to connect a grounded signal source to a
DAQPad-MIO-16XE-50 channel configured for NRSE mode.
Figure 3-7.
Single-Ended Input Connections for Ground-Referenced Signals
Common-Mode Signal Rejection Considerations
Figures 3-4 and 3-7 show connections for signal sources that are
already referenced to some ground point with respect to the
DAQPad-MIO-16XE-50. In these cases, the PGIA can reject any voltage
caused by ground potential differences between the signal source and the
DAQPad-MIO-16XE-50. In addition, with differential input connections,
the PGIA can reject common-mode noise pickup in the leads connecting
the signal sources to the DAQPad-MIO-16XE-50. The PGIA can reject
common-mode signals as long as V
in
+ and V
in
– are both within ±11 V of
AIGND. The DAQPad-MIO-16XE-50 has the additional restriction that
Selected Channel in NRSE Configuration
PGIA
Programmable
Gain
Instrumentation
Amplifier
+
+
–
–
+
–
Input Multiplexers
AISENSE
AIGND
+
–
ACH+
ACH–
V
m
Common-
Mode
Noise and
Ground
Potential
Ground-
Referenced
Signal
Source
Measured
Voltage
I/O Connector
V
s
V
cm