Electrical Interfaces
AGD301 Product Manual Rev.2.0
Page 46
3.4.14 I/O Interfaces – Circuitry
Isolated Digital Inputs
Figure 23. Isolated digital inputs
Isolated digital inputs are organized as groups with a dedicated common pin. This enables
connection to different voltage supplies. Each group is fully isolated and independent of the
other groups.
The AGD301 has three groups of inputs: digital inputs 1 to 6, digital inputs 7 to 12, and digital
inputs 13 to 18.
Each group can be connected as NPN or PNP interfaces, depending on the wiring of the group’s
common pin. If the common pin is connected to power (5V to 28V), then the inputs of this group
can be used with external NPN devices (external current sinking devices). If the common is
connected to the GND of some external power, then the inputs can be used with external PNP
devices (external current sourcing devices).
The input circuit of the opto-couplers includes two diodes. This enables use as NPN or PNP.
One group can be wired to interface external NPN devices and another group can be wired to
interface PNP devices. However, within a group, all interfaces (NPN or PNP) must be the same, as
they are based on the connection of the group’s common pin.
Isolated Digital Outputs
Figure 24. Isolated digital outputs
The AGD301 has 5 groups of digital output , digital outputs 1 to 3, 4 to 6, 7 to 9, 10 to 13 , and 14
to 17.
The digital output interface circuit is identical for all 17 outputs.
