Measurement Computing USB-1808X, Руководство пользователя

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USB-1808X User's Guide Specifications
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Analog input/output calibration
Table 9. Analog I/O calibration specifications
Parameter Specification
Warm-up time 15 minutes recommended min
Calibration method Factory calibration
Calibration interval 1 year
Digital input/output
Table 10. Digital I/O specifications
Parameter Specification
Digital type CMOS
Number of I/O 4
Configuration Each bit may be configured as input (power on default) or output
Pull-up configuration The port has 47 kΩ resistors configurable as pull -up or pull-down (default) via internal
jumper (DIO).
Digital I/O transfer rate
(system-paced, asynchronous)
33 to 8,000 port reads/writes or single bit reads/writes per second typ,
system dependent.
Digital I/O transfer rate
(synchronous)
0.023 Hz to 200 kHz input, 500 kHz output, based on the internal clock speed of
100 MHz
Scan clock source for input Internal input scan clock or external input scan clock (ICLKI pin)
Scan clock source for input Internal output scan clock or external output scan clock (OCLKI pin)
Trigger source

ITRIG for inputs, OTRIG for outputs (see External trigger on page 24)

Digital pattern detection for inputs and outputs (see Pattern trigger on page 24)
Input high voltage 2.0 V min
5.5 V absolute max
Input low voltage 0.8 V max
–0.5 V absolute min
0 V recommended min
Output high voltage 4.4 V min (IOH = –50 µA)
3.76 V min (IOH = –2.5 mA)
Output low voltage 0.1 V max (IOL = 50 µA)
0.44 V max (IOL = 2.5 mA)
Output current ±2.5 mA max