Digital Input/Output; External Trigger; External Clock Input/Output - Measurement Computing USB-1616FS User Manual

USB-1616FS User's Guide

Digital input/output

Digital type
Number of I/O
Configuration
Pull up/pull-down
configuration
Digital I/O transfer rate
(software paced)
Input high voltage
Input low voltage
Output high voltage (IOH
= -2.5 mA)
Output low voltage (IOL
= 2.5 mA)
Power on and reset state

External trigger

Parameter
Trigger Source (Note
3)
Trigger mode
Trigger latency
Trigger pulse width
Input high voltage
Input low voltage
Input leakage
current
TRIG_IN is a Schmitt trigger input protected with a 1.5 k Ohm series resistor.
Note 3:

External clock input/output

Parameter
Pin name
Pin type
Software selectable
direction
Input Clock Rate
Clock pulse width
Input leakage current
Input high voltage
Input low voltage
Output high voltage (Note
4)
Output low voltage (Note
4)
CMOS
8 (DIO0 through DIO7)
Independently configured for input or output
All pins pulled up to USB VBUS via 47 K resistors (default). Positions available for
pull down to ground (GND). Hardware selectable via zero ohm resistors as a factory
option.
System dependent, 33 to 1000 port reads/writes or single bit reads/writes per second
typ.
2.0 V min., 5.5 V absolute max.
0.8 V max., -0.5 V absolute min.
3.8 V min.
0.7 V max.
Input
Conditions Specification
External digital TRIG_IN
Software Edge Sensitive: user configurable for CMOS compatible rising
selectable (default) or falling edge.
10 µs max.
1 µs min
4.0 V min, 5.5 V absolute max.
1.0 V max,-0.5 V min
±1.0µA
Conditions Specification
SYNC
Bidirectional
Output Outputs internal A/D pacer clock.
Input Receives A/D pacer clock from external source. Rising edge
sensitive.
50kHz, maximum
Input 1µs min.
Output 5µs min.
±1.0 µA
4.0V min., 5.5V absolute max.
1.0V max., -0.5V absolute min.
IOH = - 3.3V min.
2.5mA
No load 3.8V min.
IOL = 2.5mA 1.1V max.
No load 0.6V max.
4-4
Specifications