National Instruments 6023E - Manual (Page 44)

Chapter 4 Signal Connections
6023E/6024E/6025E User Manual 4-14 ni.com
Differential Connections for Ground-Referenced
Signal Sources
Figure 4-5 shows how to connect a ground-referenced signal source to a
channel on the device configured in DIFF input mode.
Figure 4-5. Differential Input Connections for Ground-Referenced Signals
With this type of connection, the PGIA rejects both the common-mode
noise in the signal and the ground potential difference between the signal
source and the device ground, shown as V
cm
in Figure 4-5.
Ground-
Referenced
Signal
Source
Common-
Mode
Noise and
Ground
Potential
Input Multiplexers
AISENSE
V
m
Measured
Voltage
AIGND
–
+
–
+
+
–
–
+
I/O Connector
ACH+
ACH–
Selected Channel in DIFF Configuration
PGIA
Programmable Gain
Instrumentation
Amplifier
Vs
Vcm