Analog Input/Output Calibration; Digital Input/Output - Measurement Computing USB-1808X User Manual

USB-1808X User's Guide

Analog input/output calibration

Parameter
Warm-up time
Calibration method
Calibration interval

Digital input/output

Parameter
Digital type
Number of I/O
Configuration
Pull-up configuration
Digital I/O transfer rate
(system-paced, asynchronous)
Digital I/O transfer rate
(synchronous)
Scan clock source for input
Scan clock source for input
Trigger source
Input high voltage
Input low voltage
Output high voltage
Output low voltage
Output current
Table 9. Analog I/O calibration specifications
Specification
15 minutes recommended min
Factory calibration
1 year
Table 10. Digital I/O specifications
Specification
CMOS
4
Each bit may be configured as input (power on default) or output
The port has 47 kΩ resistors configurable as pull-up or pull-down (default) via internal
jumper (DIO).
33 to 8,000 port reads/writes or single bit reads/writes per second typ,
system dependent.
0.023 Hz to 200 kHz input, 500 kHz output, based on the internal clock speed of
100 MHz
Internal input scan clock or external input scan clock (ICLKI pin)
Internal output scan clock or external output scan clock (OCLKI pin)
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)

2.0 V min
5.5 V absolute max
0.8 V max
–0.5 V absolute min
0 V recommended min
4.4 V min (IOH = –50 µA)
3.76 V min (IOH = –2.5 mA)
0.1 V max (IOL = 50 µA)
0.44 V max (IOL = 2.5 mA)
±2.5 mA max
21
Specifications