National Instruments PXI-7340, User Manual And Specifications

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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 k
Ω
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 Keep trigger input, shutdown input, and breakpoint output signals and
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 Excessive input voltages can cause erroneous operation and/or
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.
Figure 4-6. Trigger Input Circuit
Figure 4-7. Shutdown Input Circuit
74FCT244
1 k
Ω
1/ 8 W
From the extern a l
connector trigger pin s
To the trigger
circ u it s
DGND
Vcc
3 . 3 k
Ω
74FCT244
1 k Ω
1/ 8 W
From the extern a l
connector s h u tdown pin
To the s h u tdown
circ u it s
DGND
Vcc
3 . 3 k
Ω