USB-1608FS User's Guide
20
Table 3. Accuracy components - All values are (±)
Range
% of Reading
Gain error at FS (mV)
Offset (mV)
±10 V
0.04
4.00
1.66
±5 V
0.04
2.00
0.98
±2 V
0.04
0.80
0.51
±1 V
0.04
0.40
0.28
Table 4 summarizes the noise performance for the USB-1608FS. Noise distribution is determined by gathering
50 k samples with inputs tied to ground at the user connector. Samples are gathered at the maximum specified
sampling rate of 50 kS/s.
Table 4. Noise performance
Range
Typical counts
LSBrms
±10 V
10
1.52
±5 V
10
1.52
±2 V
11
1.67
±1 V
14
2.12
Digital I/O
Table 5. Digital I/O specifications
Parameter
Specification
Digital type
CMOS
Number of I/O
8 (DIO0 through DIO7)
Configuration
Independently configured for input or output
Pull-up/pull-down configuration
All pins pulled up to 5V via 47 k
Ω resistors (default).
Hardware revisions E and later may be changed to pull-down using an internal
user-configurable jumper.
Previous revisions can be configured for pull-down at the factory.
Input high voltage threshold
2.0 V min
Input high voltage limit
5.5 V absolute max
Input low voltage threshold
0.8 V max
Input low voltage limit
–0.5 V absolute min
0 V recommended min
Output high voltage
(IOH = –2.5 mA)
3.8 V min
Output low voltage
(IOL = 2.5 mA)
0.44 V max
Power on and reset state
Input
