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3.2.4.2 DUT FAIL signal
This is an input signal. It can be used to indicate that a DUT failure has occured. Once this signal input is pulled
low the present pulse generation pattern will be aborted and testing will end. The AutoStar software can
automatically detect the state of the DUT FAIL signal input and will stop the program execution automatically
if it detects a low signal.
The DUT FAIL input signal is optically isolated. The schematic for this input is as follows.
1K
+5 V
GND
Pin 1
Pin 5
GND
GND
+5 V
1k
Pin 2
Pin 1
Optically
isolated
Control
(internal)
Picture 3-17: Schematic for the DUT FAIL signal input.
3.2.4.3 CRO trigger
This is an output signal. Its main purpose is for triggering an oscilloscope. The CRO trigger output will go low
at the start of a pulse, or burst of pulses. If a burst of pulses is being generated with the 3a or 3b generators
the trigger output will stay low for the duration of the burst. The CRO trigger is an optically isolated output and
the schematic for this output is as follows.
1K
+5 V
GND
Pin 1
Pin 5
GND
GND
+5 V
1k
Pin 2
Pin 1
Optically
isolated
Control
(internal)
Picture 3-18: Schematic for the CRO trigger output signal.
