NI DAQPad-MIO-16XE-50, User Manual

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Chapter 2 Installing and Configuring the DAQPad-MIO-16XE-50
© National Instruments Corporation 2-5 DAQPad-MIO-16XE-50 User Manual
For more information about the three types of input configuration, refer to
the
Input Configurations section of Chapter 3, Connecting the Signals ,
which contains diagrams showing the signal paths for the three
configurations.
Input Polarity and Input Range
The DAQPad-MIO-16XE-50 has two input polarities—unipolar and
bipolar. Unipolar input means that the input voltage range is between
0 and V
ref
, where V
ref
is a positive reference voltage. Bipolar input
means that the input voltage range is between –V
ref
and +V
ref
. The
DAQPad-MIO-16XE-50 has a unipolar input range of 10 V (0 to 10 V)
and a bipolar input range of 20 V (±10 V).
The software-programmable gain on this board increases its overall
flexibility by matching the input signal ranges to those that the ADC can
accommodate. The DAQPad-MIO-16XE-50 has gains of 1, 2, 10, and 100
and is suited for a wide variety of signal levels. With the proper gain setting,
you can use the full resolution of the ADC to measure the input signal.
Table 2-2 shows the overall input range and precision according to the input
range configuration and gain used. You can program polarity and range
settings on a per channel basis so that you can configure each input channel
uniquely.
Table 2-1. Available Input Configurations for the DAQPad-MIO-16XE-50
Configuration Description
DIFF A channel configured in DIFF mode uses
two analog channel input lines. One line connects
to the positive input of the board programmable
gain instrumentation amplifier (PGIA), and the
other connects to the negative input of the PGIA.
RSE A channel configured in RSE mode uses
one analog channel input line, which connects to
the positive input of the PGIA. The negative input
of the PGIA is internally tied to analog input
ground (AIGND).
NRSE A channel configured in NRSE mode uses
one analog channel input line, which connects to
the positive input of the PGIA. The negative input
of the PGIA connects to the analog input sense
(AISENSE) input.