Hall element & magnets

Hall element

The Hall device made according to the Hall effect uses the magnetic field as the working medium to convert the motion parameters of the object into the form of digital voltage output, so that it has the functions of sensing and switching. According to the function of Hall element, it can be divided into Hall linear element and Hall switch element. The former outputs analog quantity and the latter outputs digital quantity.

01. Hall linear element

The internal structure of the linear Hall element mainly includes three parts: a voltage regulator circuit, a linear Hall element, and an operational amplifier. The input is the magnetic induction intensity, and the output is a voltage proportional to the input. This type of circuit has high sensitivity and excellent linearity, and is suitable for various magnetic field detection. The linear Hall element triggers a parabolic stroke according to the strength of the magnetic field. For example, the acceleration handle of an electric car uses a linear Hall element, which can increase the speed from 0 to the maximum according to the change of the magnetic field, but the magnetic field strength exceeds a certain interval. When you click, the speed always remains the same.

02. Hall switch

The switch-type Hall sensor is composed of a voltage regulator, a Hall element, an amplifier, a Schmitt trigger and an output stage.

The picture comes from the Internet

When the magnetic object moves closer to the Hall switch, the Hall element on the detection surface of the switch changes the state of the internal circuit of the switch due to the Hall effect, thereby identifying the presence of magnetic objects nearby, and then controlling the on or off of the switch. The detection object of this proximity switch must be a magnetic object.