Unipolar Hall Switches

unipolar hall switch is a semiconductor device that is used to detect the presence or absence of a magnetic field.  Unipolar Hall switches are called “unipolar” because they are primarily sensitive to one polarity of the magnetic field.
CategoryModelOperating VoltageReverse VoltageMagnetic Operate PointMagnetic Release PointOperating Temperature RangePackageAlternative toDocument
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How a unipolar Hall switch typically works:

Hall Element: The core component of a Hall switch is a Hall element, which is usually a small piece of semiconductor material with a current flowing through it. When a magnetic field is applied perpendicular to the Hall element, it generates a voltage difference across its terminals.

Threshold Sensing: Unipolar Hall switches are designed to respond to a specific magnetic field polarity, either North (N) or South (S). They are sensitive to the presence or absence of the magnetic field of that polarity.

Switching Output: The output of the Hall switch is binary, meaning it is either in an “on” or “off” state, depending on whether the magnetic field of the specified polarity is present or not. When the magnetic field reaches a certain strength (typically the threshold level), the Hall switch will change its output state.


Unipolar Hall switches are commonly used in various applications, such as proximity sensors, position sensors, speed sensors, and brushless DC motor control. They provide a digital output signal that can be easily interfaced with microcontrollers and other digital electronics for control and automation purposes. The threshold level and sensitivity of the Hall switch can often be adjusted to suit the specific requirements of the application.