National Instruments WSN-3226, User Manual And Specifications

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© National Instruments Corporation 21 NI WSN-3226 User Guide and Specifications
Note You can connect only one external DIO PWR supply to the NI WSN-3226.
The power supply provides the current for the devices you connect to the NI WSN-3226. Connect the
power supply positive lead to DIO PWR terminal and the power supply negative lead to one of the
DGND terminals. The DIO PWR terminal on the NI WSN-3226 is internally connected to each digital
channel. Refer to the
Specifications section for information about the power supply voltage range.
Note The Drive High (Sourcing) and Drive High and Low (Sinking and Sourcing) modes require an
external power supply connected to the DIO PWR terminal.
Drive High (Sourcing)
Drive High (Sourcing) mode is for devices that require high side drive or a sourcing output. When using
this 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.
• Writing a digital value of 1 turns on the channel, and 0 turns off the channel.
• The channel is high impedance when the channel is turned off (0).
Figure 18.
Connecting a Device to the NI WSN-3226 in Drive High Mode
Drive Low (Sinking)
Drive Low (Sinking) mode is for devices that require low side drive or a sinking output. When using
this mode:
• The DIO x terminal is pulled to DGND when you turn on the channel.
• Writing a digital value of 0 turns on the channel, and writing a digital value of 1 turns off the
channel.
DIO x
DGND
Extern a l
Power
Su pply
+
–
Device
DIO PWR
High S ide S witch
DI
(Intern a l)
NI W S N- 3 226