Delta Tau PMAC Pack, Hardware Reference Manual

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PMAC-Pack
Getting Started 33
Figure 2-7. General Purpose Output Connected in the Optional Sourcing Configuration
Input Source/Sink Control
The method of interconnection to the general purpose inputs (JOPT INPUTS) determines the
sinking/sourcing configuration of the eight inputs. In the sinking configuration, the inputs are biased to
+V for the “OFF” state, and must be pulled low for the “ON” state. In the sourcing configuration, the
inputs are biased to ground for the “OFF” state, and must be pulled high for the “ON” state. In either case,
a high voltage is interpreted as a ‘0’ by the PMAC software, and a low voltage is interpreted as a ‘1’.
Figure 2-8 illustrates connection of an input in a Sinking configuration and Figure 2-9 illustrates the
connection of an input in sourcing configuration. When the switch is closed, current flows through the
switch and into the PMAC-Pack’s opto-isolator to the Limit Return which is tied to common. When the
switch is closed, current is pulled through the opto-isolator in the PMAC-PACK to ground.
The general purpose inputs are capable of operation at 12 to 24 DC voltage levels. If you desire to
maintain full isoV should be a separate voltage source. It is possible to operate using the +12V
available on pin 2 of each “Flags” connector as the voltage source. However, it should be noted that this
defeats the isolation circuitry causing the general input circuitry to be referenced to PMAC’s analog
ground (AGND) which is typically shared by the amplifier.
Figure 2-8. Connection of Input in Sinking Configuration