National Instruments VXI-MIO Series , Considerations for Selecting Input Ranges

Chapter 3 Hardware Overview
VXI-MIO Series User Manual 3-6  National Instruments Corporation
the overall input range and precision according to the configuration
and gain used.
Considerations for Selecting Input Ranges
Which input polarity and range you select depends on the expected
range of the incoming signal. A large input range can accommodate a
large signal variation but reduces the voltage resolution. Choosing a
smaller input range improves the voltage resolution but may result in
the input signal going out of range. For best results, you should match
the input range as closely as possible to the expected range of the input
signal. For example, if you are certain the input signal will not be
negative (below 0 V), unipolar input polarity is best. However, if the
signal is negative or equal to zero, using unipolar input polarity will
yield inaccurate readings.
Table 3-3. Actual Range and Measurement Precision, VXI-MIO-64XE-10
Range
Configuration Gain Actual Input Range Precision
1
0 to +10 V 1.0
2.0
5.0
10.0
20.0
50.0
100.0
0 to +10 V
0 to +5 V
0 to +2 V
0 to +1 V
0 to +500 mV
0 to +200 mV
0 to 100 mV
152.59 µ V
76.29 µ V
30.52 µ V
15.26 µ V
7.63 µ V
3.05 µ V
1.53 µ V
-10 to +10 V 1.0
2.0
5.0
10.0
20.0
50.0
100.0
-10 to +10 V
-5 to +5 V
-2 to +2 V
-1 to +1 V
-500 to +500 mV
-200 to +200 mV
-100 to +100 mV
305.18 µ V
152.59 µ V
61.04 µ V
30.52 µ V
15.26 µ V
6.10 µ V
3.05 µ V
1
The value of 1 LSB of the 12-bit ADC; that is, the voltage
increment corresponding to a change of one count in the ADC
12-bit count.
Note: See Appendix A , Specifications, for absolute maximum
ratings.