If I had an array of these sensors - each one reading the light from a single scanning laser beam (ie only one sensor is ever illuminated at a given moment)
Can I just tie all the output lines together, or is there a more correct way?
On a scope trace I've noticed that each sensor works well when used alone, but when I combine the outputs the reliability seems to decrease.
Dave
You should not connect these outputs directly together, because each is trying to produce its specific voltage, regardless of the load connected. Unfortunately, each is a bit better at producing a low voltage output than a high (light signal) output, so if only one is illuminated at a time, the dark one wins that tug of war. Connect them through a pair of series resistors, say, 10k ohms, each.
This will average the two outputs, accurately, though since only one is illuminated at a time, the result will still be lower than either alone.
A less accurate way to get a signal that is the larger of the two is to connect them together through a pair of Schottky signal diodes, anodes to the outputs cathodes tied together. This will lose the forward drop of a diode, but output the most positive signal from the pair at all times.
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