Chapter 4
Signal Connections
4-12
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Differential Connections for Ground-Referenced
Signal Sources
Figure 4-4 shows how to connect a ground-referenced signal source to a
channel on the device configured in DIFF input mode.
Figure 4-4.
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 4-4.
Ground-
Referenced
Signal
Source
Common-
Mode
Noise and
Ground
Potential
Input Multiplexers
AISENSE
Instrumentation
Amplifier
V
m
Measured
Voltage
AIGND
–
+
–
+
V
s
V
cm
+
–
–
+
I/O Connector
ACH+
ACH–
Selected Channel in DIFF Configuration
PGIA
Programmable Gain
