Configuration and Installation Chapter 2
PC-DIO-96 User Manual 2-12 © National Instruments Corporation
Digital I/O Signal Connections
Pins 1 through 48 and pins 51 through 98 of the I/O connector are digital I/O signal pins. The
following specifications and ratings apply to the digital I/O lines.
Absolute maximum voltage rating -0.5 to +5.5 V with respect to GND
Digital input specifications (referenced to GND):
Input logic high voltage 2.2 V minimum 5.3 V maximum
Input logic low voltage -0.3 V minimum 0.8 V maximum
Maximum input current (0 < Vin < 5 V) -1.0
µ
A minimum 1.0 µA maximum
Digital output specifications (referenced to GND):
Output logic high voltage 3.7 V minimum 5.0 V maximum
at Iout = -2.5 mA
Output logic low voltage 0.0 V minimum 0.4 V maximum
at Iout = 2.5 mA
Output current 4.0 mA minimum —
at VOL = 0.5 V
Output current 4.0 mA minimum —
at VOH = 2.7 V
Figure 2-7 depicts signal connections for three typical digital I/O applications.