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Operation Theory
4.1.2
DAQ/PXI-2005/2006 AI Data Format
The data format of the acquired 16-bit A/D data is Binary coding. Table 7
and 8 illustrate the valid input ranges and the ideal transfer characteristics.
The converted digital codes for DAQ\PXI-2005/2006 are 16-bit and direct
binary, and here we present the codes as hexadecimal numbers.
Description
Bipolar Analog Input Range
Digital code
Full-scale Range ±10V
±5V
±2.5V
±1.25V
Least significant
bit
305.2uV
152.6uV
76.3uV
38.15uV
FSR-1LSB
9.999695V 4.999847V 2.499924V 1.249962V
FFFF
Mi1LSB
305.2uV
152.6uV
76.3uV
38.15uV
8001
Midscale
0V
0V
0V
0V
8000
Midscale -1LSB
-305.2uV
-152.6uV
-76.3uV
-38.15uV
7FFF
-FSR
-10V
-5V
-2.5V
-1.25V
0000
Table 7: Bipolar analog input range and the output digital code on the
DAQ/PXI-2005/2006
Description
Unipolar Analog Input Range
Digital code
Full-scale
Range
0V to 10V
0 to +5V
0 to +2.5V
0 to +1.25V
Least signifi-
cant bit
152.6uV
76.3uV
38.15uV
19.07uV
FSR-1LSB
9.999847V 4.999924V
2.499962V
1.249981V FFFF
Midscale
+1LSB
5.000153V 2.500076V
1.250038V
0.625019V 8001
Midscale
5V
2.5V
1.25V
0.625V
8000
Midscale
-1LSB
4.999847V 2.499924V
1.249962V
0.624981V 7FFF
-FSR
0V
0V
0V
0V
0000
Table 8: Unipolar analog input range and the output digital code on
the DAQ/PXI-2005/2006