Measurement Computing Data Translation DT9857, User Manual

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Appendix A
150
Digital I/O Specifications
Table 26 lists the specifications for the digital I/O subsystems on the DT9857 and DT9857E
modules.
Table 26: Digital I/O Specifications
Feature DT9857 and DT9857E Specifications
Number of digital I/O lines 16 (8 in, 8 out)
Number of ports 2 (8 bits each)
Input voltage range 0 to 3.3 V; 5 V tolerant
Logic sense Positive true
Inputs
Input type:
Input logic load:
High input voltage:
Low input voltage:
Low input current:
Termination: Level-sensitive
1 LVTTL
2.0 V minimum
0.8 V maximum
0.2 mA maximum
22 k
Ω
pull-up to 3.3 V
Outputs
Output type:
High output:
Low output:
High output current:
Low output current:
Short circuit protected: LVTTL
2.4 V minimum
0.4 V maximum
–10 mA maximum
4 mA maximum
33 mA
Clocked with sample clock Yes, if included in the analog input or analog
output channel list
Software I/O selectable No