©
National Instruments Corporation
A-1
A
Specifications
This appendix lists the specifications of the NI 781
x
R. These specifications
are typical at 25 °C unless otherwise noted.
Digital I/O
Number of channels ............................... 160 input/output
Compatibility ......................................... TTL
Digital logic levels
Maximum output current
I
max
(sink) ........................................ 5.0 mA
I
max
(source) .................................... 5.0 mA
Input leakage current
.............................. ±
10
µ
A
Power-on state........................................ Programmable by line
Data transfers ......................................... Interrupts, programmed I/O
Protection
Input ................................................ –0.5 to 7.0 V
Output ............................................. Short-circuit (up to eight lines
can be shorted at a time)
Level
Min
Max
Input low voltage (
V
IL
)
Input high voltage (
V
IH
)
0.0 V
2.0 V
0.8 V
5.5 V
Output low voltage (
V
OL
),
where
I
OUT
= –
I
max
(sink)
Output high voltage (
V
OH
),
where
I
OUT
=
I
max
(source)
—
2.4 V
0.4 V
—
