National Instruments WSN-3230, User Manual And Specifications

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© National Instruments Corporation 23 NI WSN-3230/3231 User Guide and Specifications
3V TTL Logic (Open-Collector with Pull-Up)
The 3V TTL Logic (Open-Collector with Pull-Up) mode can be used to connect to 3 V and 5 V logic
inputs with TTL Logic compatible thresholds. When using this mode:
• The DIO x terminal is pulled-up to 3 V through a pull-up resistor for a DIO output value of 1 and
driven low to ground for a DIO output value 0.
• The DIO line is read with 3V TTL Logic input thresholds.
• A supply voltage is not required on DIO PWR.
Figure 21. Connecting a Device to the NI WSN-3230/3231 in 3V TTL Logic Mode
Drive High and Low (Sinking and Sourcing)
When using Drive High and Low (Sinking and Sourcing) mode:
• Connect the device to DIO x and connect the device common to the DGND terminal corresponding
to that DIO x terminal.
• The DIO x terminal is driven to the voltage supplied to DIO PWR when you turn on the channel,
and is driven to DGND when you turn off the channel.
• If a supply voltage is not connected to DIO PWR, it operates as if it is set to the Drive Low (Sinking)
mode.
• Writing a digital value of 1 turns on the channel and writing a 0 turns the channel off.
Figure 22. Connecting a Device to the NI WSN-3230/3231 in Drive High and Low Mode
DGND
Extern a l
Power
Su pply
+
–
DIO x
Low S ide
S witch
DI
(Intern a l)
NI W S N- 3 2 3 0/ 3 2 3 1
TTL Device
TTL
P u ll Up
3 V
DIO x
DGND
Extern a l
Power
Su pply
+
–
Device
DIO PWR
High S ide S witch
Low S ide S witch
DI
(Intern a l)
NI W S N- 3 2 3 0/ 3 2 3 1