Chapter 3
Connecting the Signals
DAQPad-MIO-16XE-50 User Manual
3-20
ni.com
Figure 3-8.
RTD Connection Using External Current Excitation
Configure the AI channels for differential input mode. You can configure
the AI for either a unipolar or bipolar polarity. The signal sources are not
floating; therefore, do not connect bias resistors between the signal sources
and AIGND. The voltage potential at IEX– varies between 1.7 and 0.1 V
from 0 to 55 °C. You must take this voltage into account when realizing
the common-mode signal rejection considerations discussed in the
Common-Mode Signal Rejection Considerations
section.
+ Measure
– Voltage
PGIA
+
V
m
ACH<8 ..15>
ACH<0 ..7>
DAQPad-MIO-16XE-50
DAQPad-TB-52
ACH8
IEX–
IEX+
ACH0
ACH15
ACH7
Thermistor for
Cold-junction
Sensing
IEX
ON
OFF
RTD1
RTD2
I = 100 µA
AIGND
Instrumentation
Amplifier
–