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Chapter 3
Signal Connections
NI 951x User Manual
3-18
ni.com
Caution
Do
not
connect digital outputs to +5 V input circuitry in either sinking or sourcing
configuration.
Tip
Refer to the
Signal Connection Recommendations
section of Chapter 4,
Accessory
and Cable Connections
, for additional wiring and cabling recommendations.
Figure 3-17 shows an example of wiring the digital outputs to a sinking
input device. Figure 3-18 shows an example of wiring the digital outputs to
a sourcing input device.
Figure 3-17.
Digital Output Circuit Configured for Sourcing
Figure 3-18.
Digital Output Circuit Configured for Sinking
Drive Enable or
Digital Output
COM
NI 951x
NI 951x V
sup
NPN (Sinking)
Input Device
Configured
For Sourcing
Sinking
Circuit
V–
(Reference)
In
Drive Enable or
Digital Output
V+
V+
Drive Enable or
Digital Output
COM
NI 951x
NI 951x V
sup
PNP (Sourcing)
Input Device
Configured
For Sinking
Sourcing
Circuit
V–
(Reference)
In
Drive Enable or
Digital Output