I'm new here and to the electronics world, so my question may be dumb one! I have multiple Hall Sensors (A3144) that I wire to the digital inputs of my arduino: Hall sensor 3144

I am able to test in the code if each one detects a magnet (when the input is LOW).

However I have 5 Hall Sensors and in my use case the only information I need is if they are all detecting a magnet or not (so 0 when they all detect a magnet and 1 if at least one sensor does not detect a magnet).

Is it possible to put the sensors in parallel in order to have only one input wire?

  • \$\begingroup\$ What kind of input? Digital? Analog? \$\endgroup\$
    – Eugene Sh.
    Jul 8, 2016 at 14:52
  • \$\begingroup\$ A multiplexer with some logic gate could be the solution here. \$\endgroup\$
    – MathieuL
    Jul 8, 2016 at 15:39

1 Answer 1


Wire OR each output through a diode to produce a common output node (connected to your arduino input) and have a light pull-down resistor such as 10k. If any device is producing a high output it will force the common output to remain high (minus 0.7 volts due to the diode). All devices have to output zero to take take the common output low.


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