I am designing the Vishay VCNL4010 proximity sensor into one of my PCBs. This sensor has an interrupt pin that I don't need to use. Is it OK to just leave this pin floating ("unconnected"), or will this cause problems somehow?
Electronic – What to do with unused pin
pcbpins
Best Answer
Normally I'd say it won't be a problem: it's an output pin, so it won't be floating as the device itself will drive it.
However, if we look at the datasheet, page 5, first note:
If we look at this application note, Designing VCNL3020 into an Application, page 2:
I suppose that this is only needed when this line is actually used. However, it's always good to follow the datasheet, and that extra resistor will still fit in your circuit, hopefully. So I'd recommend you to use a pull-up resistor between 10kOhm and 100kOhm (as suggested in the datasheet excerpt) to the input voltage.