Hall Effect Sensor Pro Preview

What Is a Hall Effect Sensor?

A Hall Effect Sensor is a tiny electronic sensor that can detect magnets. It can tell when a magnet gets close and send a signal to other electronics, like an Arduino or a light. Think of it like a switch that turns on when a magnet is near.

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  • #2493
  • 12 Sep 2025

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How Does It Work?

A Hall sensor has a thin strip of conductive material inside. When current flows through it and a magnetic field is applied, it produces a small voltage that can be measured:

  • No magnetic field → 0 or base voltage

  • South pole near sensor → Higher voltage (or logic LOW in digital type)

  • North pole near sensor → Lower voltage (or logic HIGH in digital type)

Applications of Hall Effect Sensors:

  • Automotive: Detect crankshaft/camshaft position, wheel speed (ABS), ignition timing.

  • Proximity Sensors: Open/close detection in doors or lids.

  • Speed Measurement: Counting rotations in fans, motors, or wheels.

  • Current Sensing: Non-contact current measurement in wires or PCBs.

  • Position Sensing: Used in joysticks, gear shifters, and robotics.

Tips and Troubleshooting:

  • No output change? Make sure the magnet’s correct pole is facing the sensor.

  • Sensor always HIGH? Some sensors need a pull-down resistor, or your magnet may not be strong enough.

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