ADLINK USB-2401 - Manual (Page 45)

Operation 35
USB-2401
Figure 3-10: 2-Wire Resistance Connection
3.4 AI Data Format
The acquired 24-bit A/D data is 2’s complement coded data for-
mat. Valid input ranges and optimum transfer characteristics are
as shown.
Table 3-1: Analog Input Range and Output Digital Code
Description Bipolar Analog Input Range
Digital
Code
Full-scale
range ±25 V ±12.5 V ±2.5 V ±0.3125V N/A
Least
significant bit 2.98uV 1.49uV 0.298uV 0.037uV N/A
FSR-1LSB 24.999997
V 12.4999985
V 2.4999997
V 0.3124999V 7FFFFF
Midscale
+1LSB 2.98uV 1.49uV 0.298uV 0.037 uV 000001
Midscale 0 V 0 V 0 V 0 V 000000
Midscale
-1LSB -2.98uV -1.49uV -0.298uV -0.3124999uV FFFFFF
-FSR -25 V -12.5 V -2.5 V -0.3125V 800000
ADC MUX
Resistor
X
X
SC +
SC -
0.05mA USB-2401