Each channel has a DO pin to which you can connect a digital input device. The 32 digital output channels are internally referenced to COM.
You must connect an external power supply to the NI 9476. The power supply provides the current for the output channels. Connect the positive lead of the power supply to the supply pin, Vsup, and the negative lead of the power supply to the common pin, COM. Refer to the Specifications section for information about the power supply voltage range.
Note The Vsup pins are internally connected. You can connect only one external voltage supply to the device.
Caution Do not remove or insert modules if the external
power supply connected to the Vsup powered on.
and COM pins is
The NI 9476 has current sourcing outputs, meaning the DO pin is driven to Vsup when the channel is turned on.
© National Instruments Corp.
NI 9476 Operating Instructions and Specifications