A Hall configurator is a transducer that changes its output voltage in response to a magnetic field. Hall configurator are used in proximity switching, positioning, speed sensing, and current sensing applications. The Hall effect principle is named after physicist Edwin Hall. In 1879 he discovered that by introducing a conductor or semiconductor through which current flows in one direction perpendicular to a magnetic field, it is possible to measure voltage perpendicular to the current path.
In its simplest form, the sensor acts as an analog converter and returns a voltage directly. With a known magnetic field, the distance from the Hall plate can be determined. A group of sensors can be used to infer the relative position of a magnet. Electricity passed through the conductor creates a magnetic field that varies with the current, and Hall sensors can be used to measure the current without interrupting the circuit. Sensors are usually integrated with a wound core or permanent magnet surrounding the conductor to be measured.
Often hall sensors are combined with circuitry that causes the device to operate in digital (on/off) mode, and in this configuration can be referred to as a switch. They are commonly found in industrial applications and are also used in consumer equipment. For example, some computer printers use it to detect missing paper and open covers. It can also be used for keyboards if high reliability is required.
Hall sensors are commonly used to measure the speed of wheels and shafts, such as internal combustion engine ignition timing, tachometers, and anti-lock braking systems. Used in brushless DC electric motors to sense the position of permanent magnets. At the wheel in the figure with two equally spaced magnets, the voltage on the sensor will peak twice for each revolution. This arrangement is commonly used to throttle disk drives.
Hall Effect (HE) sensors are true zero-speed sensor devices that use a special solid-state transducer chip that generates an output voltage in response to a change in magnetic field. Hall Effect transducers are produced in a variety of sensitivities, configurations, and output types. analog or digital. H-sensors fall into two general categories: oriented – requires orientation relative to the direction of movement of the target, non-oriented – does not, but generally degrades performance when used with finer pitch targets. Hall configurators have their limitations. “Drag” when used with internal magnetism (zero drag designs are possible using external magnetic excitation), limited maximum sensing distance (maximum operating temperature compared to other technologies such as RF and variable magnetoresistance (VR)).
