Hall sensor: principle of operation, specificity of application and significance for the smartphone

Modern category gadgets are multitasking devices whose large-scale functionality is not always clear to the average user, and all options are not even used in standard operation. In a little more than ten years, primitive push-button telephones were modernized into cutting-edge devices that are not inferior in functionality to computer devices. In order for a modern smartphone to appear to a person in the current format, scientists, technicians, computer geniuses worked on its development and modernization, the device was supplied with peculiar blocks, systems and transmitters whose work is synchronized, characterized by coherence and functionality. In this article we will talk about the Hall sensor, which has modified more than a third of modern smartphones, consider the essence and fundamental importance of the conditioned element, the effect of its presence on the device functionality.

The purpose of the Hall sensor in the smartphone.

What is this item

The Hall sensor is a name whose purpose is not understandable to everyone, however, evoking certain memories from the course of school physics. And indeed, to determine the functionality and value of the converter, it is worthwhile to conduct a small excursion into the scientific theory from the field of physics, recall the Hall effect studied in school when passing information about magnetic fields and the processes occurring in them.

An element, or converter, whose functionality is predetermined by the Hall effect, is intended to determine the presence of a magnetic field and its physical parameters, in the form of intensity. Physical processes often do not raise questions: many people know that the sensor of the conditioned category is actively used in internal combustion engines of vehicles, aircraft jet engines and other areas of technical design. Scientists have proven that when a conductor with a constant current enters the region of the magnetic field, a transverse potential drop occurs, which the sensor detects, which is named after a scientist.

However, to understand that this is the “Hall sensor in the phone”, why the element is used in multifunctional devices and how important the converter value is for a gadget is rather difficult for a person who has no relation to the field of computerization and technology. This moment causes the need to understand what is the Hall sensor in smartphones, working on the conditioned physical effect, which will be discussed later.

How the sensor works

The functional significance of the sensor in upgraded devices is much easier than in the technical areas of exploitation. In gadgets, a device is used to fix the presence of voltage, without calculating its coefficient on the axes. On the practical side, this happens as follows: a conductor with a passing electric current is placed in the magnetic region. Physically, this process provokes the deviation of electrons to one of the sides of the plate, accumulating in parallel a negative charge. The diametrically polar side, in turn, “collects” a positive charge. This physical process lasts as long as the generated electric-class field does not compensate for the Lorentz force of the magnetic field. The potential difference, referred to in the field of physics as the Hall voltage, at the plate edges is determined by a deterministic category sensor. In smartphones, the element is implemented in the form of a microcircuit, which creates a specific signal at a specific moment, which is required to perform the programmed tasks.

The sensor functionality in the phone

Until recently, the electromagnetic catcher operating on the Hall effect principle was inherent only in the flagship category of smartphone models, inaccessible to the ordinary consumer. At the present time, almost every third device is modified with such an element; however, not every smartphone has its capabilities fully realized. The answer to the question of why a Hall sensor on a smartphone is needed stems from its functional purpose, which is to measure the parameters of an inductive electromagnetic force, with the possibility of contactless coordination of certain gadget options. The conditioned sensor is designed to perform basic tasks that are important for modern users, knowing that it is easy to understand why it is modified into gadgets:

  1. Functioning as a digital compass, which determines the possibility of positioning the device, and accordingly, implements navigation tasks and options related to the geographical location of the phone.
  2. Turning on and off the screen of the device, modified in the “book” or “folding bed” format, occurs due to the sensor fixing the distance or approaching the other side of the device.
  3. The microcontroller allows you to position the location of the gadget relative to the surface of the earth, due to which it is possible to implement the automatic screen rotation function.
  4. Automated adjustment of the image on the display, by responding to changes due to the time of day, as well as the lighting of the room in which the device is operated.
  5. Correlational relationship with some accessories, such as covers of the magnetic category, which allows to perform specific tasks: block and activate the display by closing and opening the flip cover, respectively.

It is noteworthy that the Hall effect is not completely realized in modern gadgets, since the absolute embodiment of the sensor capabilities in smartphones will affect the compactness of the device, the battery consumption and the pricing policy for devices, with its rapid growth.

Features of interaction with magnetic flips

Magnet-modified accessories are a kind of progress in the development of mobile devices for modern devices. Magnetic covers have become particularly popular: they can be sold complete with some models of gadgets, or they can be presented in a retail range, with orientation for a specific model of a smartphone or tablet. A specific feature of these accessories is the possibility of synchronized work with the phone, by means of the presence of a magnet and a Hall sensor in the flip and smartphone, respectively. The Hall sensor, modified in the phone, allows you to either completely or partially disable the display of the gadget, when you close the cover of the cover, by receiving a specific signal from the magnetic element, and to activate its work, when you open the top flip binding. Partial or absolute blocking of the screen is determined by the model of the selected accessory:

  1. Flips that have a solid top cover completely deactivate the gadget screen when closing.
  2. Covers with specific windows fragmentarily turn off the screen, while in the conditional opening, the user-relevant information is displayed, such as time, alerts, calls, date or other data needed by the smartphone owner.

Some consumers are discussing the harm for smartphones, which is the joint exploitation of mobile cases and devices, however, such an assertion has an absolute refutation from researchers, confirmed by evidence, research base. The use of magnetic covers for smart phone models equipped with a sensor that works on the basis of the Hall effect does not harm the device’s working capacity, provides the possibility of extending its battery life by saving the phone’s charge in inactive mode of operation.


Hall sensor is an integral element of many modern gadgets. Due to its operation, the capabilities of smartphones are greatly expanded, and technical progress predicts further modernization of devices with such elements, with one hundred percent revealing of the potential physical capabilities of the sensor. We will expect when technical restrictions on the implementation of the Hall potential will be minimized, and the sensor's capabilities are fully disclosed: practice shows that such prospects will open in the near future, due to the rapid progress in the field of computer and mobile technologies.