User`s guide

Operation Theory • 27
4.1.2 DAQ/PXI-2205/2206 AI Data Format
The data format of the acquired 16-bit A/D data is 2’s Complement coding.
Table 10 and 11 shows the valid input ranges and the ideal transfer
characteristics.
Description Bipolar Analog Input Range Digital code
Full-scale
Range
±10V ±5V ±2.5V ±1.25V
Least signifi
cant
bit
305.2uV 152.6uV 76.3uV 38.15uV
FSR-1LSB 9.999695V 4.999847V 2.499924V 1.249962V 7FFF
Midscale +1LSB 305.2uV 152.6uV 76.3uV 38.15uV 0001
Midscale 0V 0V 0V 0V 0000
Midscale -1LSB -305.2uV -152.6uV -76.3uV -38.15uV FFFF
-FSR -10V -5V -2.5V -1.25V 8000
Table 10: Bipolar analog input range and the output digital code on
DAQ/PXI-2205/2206
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 7FFF
Midscale +1LSB 5.000153V 2.500076V 1.250038V 0.625019V 0001
Midscale 5V 2.5V 1.25V 0.625V 0000
Midscale -1LSB 4.999847V 2.499924V 1.249962V 0.624981V FFFF
-FSR 0V 0V 0V 0V 8000
Table 11: Unipolar analog input range and the output digital code on
DAQ/PXI-2205/2206