ADLINK PXI-2006 User Manual
Page 39
Operation Theory
29
due to the variation of the conver-sion time of the A/D con-
verters.
Table 4-1 and 4-2 illustrate the ideal transfer characteristics of var-
ious input ranges of DAQ\PXI-20XX. The converted digital codes
for DAQ\PXI-2010 are 14-bit and 2’s complement, and here we
present the codes as hexa-decimal numbers. Note that the last 2
bits of the transferred data, which are the synchronous digital input
(SDI), should be ignored when retrieving the analog data.
Description
Bipolar Analog Input Range
Digital code
Full-scale Range
±10V
±5V
±2.5V
±1.25V
Least significant bit 1.22mV 0.61mV 0.305mV 0.153mV
FSR-1LSB
9.9988V 4.9994V 2.4997V
1.2499V
1FFF
Midscale +1LSB
1.22mV 0.61mV 0.305mV 0.153mV
0001
Midscale 0V
0V
0V
0V
0000
Midscale –1LSB
-1.22mV -0.61mV -0.305mV -0.153mV
3FFF
-FSR
-10V
-5V
-2.5V
-1.25V
2000
Table 4-1: Bipolar analog input range and the output digital code on DAQ/
PXI-2010 (Note that the last 2 digital codes are SDI<1..0>)
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 significant bit
0.61mV
0.305mV
0.153mV
76.3uV
FSR-1LSB
9.9994V
4.9997V
2.9999V
1.2499V
1FFF
Midscale +1LSB
5.00061V 2.50031V 1.25015V
625.08mV
0001
Midscale 5V
2.5V
1.25V
625mV
0000
Midscale –1LSB
4.99939V 2.49970V 1.24985V
624.92mV
3FFF
-FSR
0V
0V
0V
0V
2000
Table 4-2: Unipolar analog input range and the output digital code on DAQ/
PXI-2010 (Note that the last 2 digital codes are SDI<1..0>)