Hi, I have been struggling to figure out how to use a cheap IR Proximity sensor (E18-D80NK) that I bought from China on the Arduino board by connecting the sensor to the 3.3 V port.
I have 2 of the same sensor that I bought around 4 months apart. The first one (earlier one) works well when I connect to the 3.3 V supply. But the newer one does not work when I connect to the 3.3 V supply (the sensor will become always ON). It only works when I connect it to the 5V supply. The spec of sensor does state that 5V is the input voltage, but why does is work on one but not the other? does the sensitivity adjuster (small screw behind the sensor) have any effect on this? or did the manufacturer changed something in the sensor?