Applications of Hall Effect Sensors

Hall effect sensors are commonly used in a variety of applications, such as measuring voltage, current, and magnetic fields. They also provide high-resolution information that helps engineers and designers optimize their designs.

How Hall Sensors Work

Electrons in a semiconductor material move in a straight line due to the Lorentz force. When an external magnetic field is applied, this force deviates the electrons to a curved path (Fig. 2). The accumulation of negative charge electrons on one side of the semiconductor and positive charge holes on the other, creates a potential difference that can be detected by a Hall effect sensor.

Different types of Hall Sensors

There are two basic types of hall effect sensors: digital and linear. Digital output sensors have a Schmitt trigger with built-in hysteresis connected to an amplifier that produces an output when a predetermined magnetic flux density passes through the device. These devices have just two states: "ON" and "OFF".

The output of a digital Hall effect sensor increases with a stronger magnetic field and decreases with a weaker one. This increase in output can be a problem if the power supply limits the strength of the magnetic field that is passed through the Hall effect sensor. The op-amp in these digital output sensors must be designed to allow an increased magnetic field without saturating the output.

How to Detect Magnetic Fields with a Hall Sensor

The most common application for Hall effect sensors is magnetic field detection. They are used to measure the presence of magnets or their magnetic field in industrial facilities, commercial businesses, and even the automotive industry.

These sensors can also be used for magnetic leakage detection in pipes and storage tanks. They can detect the flow of magnetic fluid or rust that could cause damage to a product, or can be used for safety applications such as anti-lock braking systems on vehicles.

Other common uses for Hall sensors include tachometers, speedometers, and anti-lock braking systems in cars. In these applications, they can be programmed to signal when a certain voltage fluctuates or to transmit signals and data that help control complex machinery or vehicles.

How to Detect Magnetic Fields With a Hall Sensor

The strongest and most precise way to use a Hall sensor is by moving the magnetic field vector from the north pole to the south pole of the sensor, as shown in Figure 2. This method typically results in very accurate switch point locations. However, this mode of operation requires strong magnets and a relatively small total effective air gap, or TEAG.

Another way to detect magnetic fields with a Hall sensor is by placing a permanent biasing magnet behind the active area of the LEM current sensors. This can be done by encapsulating the Hall effect sensor in a plastic package or by using adhesive tape.

Alternatively, you can place the sensor in a metal package or add an adhesive to the top of the magnetic circuitry for a more traditional sensor. The result is a highly reliable sensor that can be mounted on a surface or in a housing for more convenient use. Check out this related post that will enlighten you more on this link: https://en.wikipedia.org/wiki/Force-sensing_resistor.