Wiring Concerns; Trigger Input, Shutdown Input, And Breakpoint Output Circuits - National Instruments PXI-7340 User Manual And Specifications

Chapter 4 Signal Connections
The breakpoint outputs are driven by open-collector TTL buffers that feature 64 mA sink
current capability and built-in 3.3 kΩ pull-up resistors to +5 V.
You can directly set and reset breakpoint outputs to use them as general-purpose digital
outputs.
Note Breakpoint outputs and trigger inputs require an encoder connection.

Wiring Concerns

Caution
their ground connections wired separately from the motor driver/amplifier signal and
encoder signal connections. Wiring these signals near each other can cause faulty
operation.
Caution
component failure.

Trigger Input, Shutdown Input, and Breakpoint Output Circuits

Figures 4-6, 4-7, and 4-8 show a simplified schematic diagram of the circuits used by the trigger
inputs, shutdown inputs, and breakpoint outputs for signal buffering.
From the external
connector trigger pins
From the external
connector shutdown pin
4-10 | ni.com
Keep trigger input, shutdown input, and breakpoint output signals and
Excessive input voltages can cause erroneous operation and/or
Figure 4-6. Trigger Input Circuit
Vcc
3.3 kΩ
1 kΩ
1/8 W
Figure 4-7. Shutdown Input Circuit
Vcc
3.3 kΩ
1 kΩ
1/8 W
74FCT244
DGND
74FCT244
DGND
To the trigger
circuits
To the shutdown
circuits