External Trigger; External Clock Input/Output - Measurement Computing usb1608fs User Manual

USB-1608FS User's Guide

External trigger

Parameter
Trigger source
Trigger mode
Trigger latency
Trigger pulse width
Input type
Schmitt trigger hysteresis
Input high voltage threshold
Input high voltage limit
Input low voltage threshold
Input low voltage limit

External clock input/output

Parameter
Pin name
Pin type
Direction, software-selectable
Input clock rate
Clock pulse width
Input clock mode
Schmitt trigger hysteresis
Input high voltage threshold
Input high voltage limit
Input low voltage threshold
Input low voltage limit
Output high voltage
Output low voltage
Table 6. External trigger specifications
Condition Specification
External digital TRIG_IN
Software-selectable Edge sensitive: user configurable for CMOS compatible
rising or falling edge.
10 µs max
1µs min
Schmitt trigger, 47 kΩ pull-down to ground
1.01 V typ
0.6 V min
1.5 V max
2.43 V typ
1.9 V min
3.1V max
5.5 V absolute max
1.42 V typ
1.0 V min
2.0 V max
–0.5 V absolute min
0 V recommended min
Table 7. External clock I/O specifications
Condition Specification
SYNC
Bidirectional
Input Receives A/D pacer clock from external source
Output Outputs internal A/D pacer clock
50 kHz, maximum
Input 1µs min
Output 5µs min
Edge sensitive: rising edge
1.01 V typ
0.6 V min
1.5 V max
2.43 V typ
1.9 V min
3.1V max
5.5 V absolute max
1.42 V typ
1.0 V min
2.0 V max
–0.5 V absolute min
0 V recommended min
4.4 V min (IOH = –50 µA)
3.80 V min (IOH = –8 mA)
0.1 V max (IOL = 50 µA)
0.44 V max (IOL = 8 mA)
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