Rigol DS1302CA User Manual page 93

3. Pass/Fail connection
The Pass/Fail connection has an optically isolated output. It needs to connect to
another circuit to fulfill the function.
Before connecting to an external circuit, make sure the maximum
voltage/current does not exceed the internal photo MOS relay‟s rating,
400V/100mA. DS1000CA series adopts the technique of Optical Isolation, and
the output device has no polarity and can be used in any circuit within the
ratings.
User‟s Guide for DS1000CA Series
Figure 2-90
Schematic Diagram of Pass/Fail output
RIGOL
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