USB-1608G Series User's Guide
Specifications
20
Accuracy
Analog input DC voltage measurement accuracy
Table 2. DC Accuracy components and specifications. All values are (±)
Range
Gain error
(% of reading)
Offset error
(µV)
INL error
(% of range)
Absolute
accuracy at
Full Scale
(µV)
Gain
temperature
coefficient
(% reading/°C)
Offset
temperature
coefficient
(µV/°C)
±10 V
0.024
915
0.0076
4075
0.0014
47
±5 V
0.024
686
0.0076
2266
0.0014
24
±2 V
0.024
336
0.0076
968
0.0014
10
±1 V
0.024
245
0.0076
561
0.0014
5
Noise performance
For the peak-to-peak noise distribution test, a differential input channel is connected to AGND at the input
terminal block, and 32,000 samples are acquired at the maximum rate available at each setting.
Table 3. Noise performance specifications
Range
Counts
LSBrms
±10 V
6
0.91
±5 V
6
0.91
±2 V
7
1.06
±1 V
9
1.36
Settling time
Settling time is defined as the accuracy that can be expected after one conversion when switching from a
channel with a DC input at one extreme of full scale to another channel with a DC input at the other extreme of
full scale. Both input channels are configured for the same input range.
USB-1608GX-2AO, USB-1608GX
Table 4. Input settling time specifications in µS, typical
Range 2 µS settling accuracy
(% FSR)
4 µS settling accuracy
(% FSR)
9 µS settling accuracy
(% FSR)
±10 V
0.1251
0.0031
0.0015
±5 V
0.0687
0.0031
0.0015
±2 V
0.0687
0.0031
0.0015
±1 V
0.0687
0.0031
0.0015
USB-1608G
Table 5. Input settling time specifications in µS, typical
Range
4 µS settling accuracy
(% FSR)
6 µS settling accuracy
(% FSR)
±10 µS settling accuracy
(% FSR)
±10 V
0.0061
0.0031
0.0015
±5 V
0.0061
0.0031
0.0015
±2 V
0.0061
0.0031
0.0015
±1 V
0.0061
0.0031
0.0015
