Multiple-Channel Scanning Considerations; Figure 3-7. Dither - National Instruments AT-MIO/AI E Series User Manual

Chapter 3 Hardware Overview
LSBs LSBs
6.0 6.0
4.0 4.0
2.0 2.0
0.0 0.0
-2.0 -2.0
-4.0 -4.0
-6.0 -6.0
0 0 100 100
a. Dither disabled; no averaging
LSBs LSBs
6.0 6.0
4.0 4.0
2.0 2.0
0.0 0.0
-2.0 -2.0
-4.0 -4.0
-6.0 -6.0
0 0 100 100
c. Dither enabled; no averaging

Multiple-Channel Scanning Considerations

AT-MIO/AI E Series User Manual
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You cannot disable dither on the AT-MIO-16XE-10, AT-AI-16XE-10,
or AT-MIO-16XE-50. This is because the resolution of the ADC is so
fine that the ADC and the PGIA inherently produce almost 0.5 LSB rms
of noise. This is equivalent to having a dither circuit that is always
enabled.
All of the AT E Series boards can scan multiple channels at the same
maximum rate as their single-channel rate; however, you should pay
careful attention to the settling times for each of the boards. The
settling time for most of the AT E Series boards is independent of the
selected gain, even at the maximum sampling rate. The settling time for
the high channel count and very high-speed boards is gain dependent,
which can affect the useful sampling rate for a given gain. No extra
settling time is necessary between channels as long as the gain is
LSBs LSBs
6.0 6.0
4.0 4.0
2.0 2.0
0.0 0.0
-2.0 -2.0
-4.0 -4.0
-6.0 -6.0
0 0 100 100
b. Dither disabled; average of 50 acquisitions
LSBs LSBs
6.0 6.0
4.0 4.0
2.0 2.0
0.0 0.0
-2.0 -2.0
-4.0 -4.0
-6.0 -6.0
0 0 100 100
d. Dither enabled; average of 50 acquisitions

Figure 3-7. Dither

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