> I have a IR-sensor with an open collector output.
> Can somebody be kind and explain how it works
> or show me with a drawing will be nice!

MOST LIKELY, when exposed to IR light above
a certain threshold, the OC pin will be pulled to
ground.  Or maybe if exposed to IR light pulsed
at a certain frequency.  Or maybe the amount
of current flowing into the OC pin will vary
depending on the amount of IR light incident to
the sensor.

It's hard to say, exactly, without more details of
the product involved.

Mike H.

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