Data Translation DT9850 Series, User Manual, Page: 90 / 104

Appendix A
90
Digital I/O Specifications
Table 27 lists the digital input and digital output specifications for the DT9850 Series modules.
Table 27: Digital Input and Digital Output Specifications
Feature Specifications
Digital logic type CMOS
Number of lines 8 digital inputs (port B);
8 digital outputs (port A)
Digital I/O transfer rate Up to 1 kHz (system dependent)
Power on and reset state Digital input
Pull-up/pull-down
configuration User-configurable on inputs
a
;
By default, all input pins floating
a. For pull-up, connect the Digital I/O Termination Select pin to the +5 V Out pin. For
pull-down, connect the Digital I/O Termination select pin to the Digital Ground pin.
Digital input loading TTL (default)
47 k
Ω
(pull-up/pull-down configuration)
Inputs
Input type:
Input load:
High-level input voltage:
Low-level input voltage:
Interrupt-on-change:
Level sensitive
Schmitt trigger
3.5 V minimum
1.5 V maximum
Digital input lines 0 to 6
Outputs
Output driver:
Output driver high voltage:
Output driver low voltage:
Push-pull logic
4.3 V minimum (IOH = –2 mA);
0.6 V maximum (IOL = 10 mA)