Modern mobile devices have a large number of auxiliary sensors that transform a regular mobile phone into a smart device with big amount functions. In addition to the accelerometer, light sensor and other sensors, many modern smartphones also have a so-called “Hall sensor”, which allows you to measure tension magnetic field. In this material, I will tell you in detail what a Hall sensor is in a phone, what the specifics of its application are, and what smartphone functions it can be especially useful for.

Hall Sensor is a measuring element (essentially a magnetometer) that determines the presence, intensity, and changes in the intensity of the magnetic field.

The sensor got its name thanks to the “Hall effect” discovered in 1879 - the emergence of a transverse potential difference that appears due to placing a conductor with direct current in a magnetic field (American physicist Edwin Hall, after whom this effect is named, experimented with skipping direct current on thin plates of gold).

The capabilities of the Hall sensor are useful in many areas of material production (in particular, in the automotive industry). Its use in the production of mobile gadgets made it possible to implement the following functions:

• Measure the magnitude of magnetic flux;
• Automatically adjust screen brightness at different levels of illumination;
• Determine a more accurate direction of movement;
• Implement contactless control (using gestures);
• Change the orientation of the image on the display of your gadget and so on.

In smartphones, the Hall sensor looks like a microcircuit that outputs a signal in the form of a zero (no signal) or a one (signal is supplied). This signal is read by the smartphone, and depending on the specific settings, the device performs one or another action.

Checking if your phone has a Hall sensor

So how do you know if there is magnetic sensor in phone? Typically, the presence of a Hall sensor in a smartphone should be indicated in technical specifications your device. If smart cases (Smart Case level) are sold for your smartphone model, then it is likely that the sensor I am considering is present in your gadget.

At the same time, most modern flagship smartphone models have the mentioned sensor built into the internal functionality of such devices. I'm sure you understand what kind of Hall sensor is in your mobile device, now let's figure out why it is needed.

Why do you need a Hall Sensor in your phone?

In the manufacture of smartphones, a simplified model of the Hall sensor is used in several main cases:

• As a digital compass. Helps in determining the positioning of the device, determining the direction of movement, contributes to more correct operation GPS;
• When working with magnetic cases. The Hall sensor responds to the opening and closing of such a case (often a flip case), accordingly turning on or off certain phone operating modes (for example, display). Accordingly, this allows you to reduce the rate of battery discharge, contributing to its more careful consumption.

• In flip phones (folding phones). In such devices, opening or closing the lid turns the device on or off;
• In other devices related to the operation of a smartphone, in particular, with glasses virtual reality Google CardBoard, where the Hall sensor is used in the operation of the only button of this accessory.

At the same time, the small size of the smartphone and the equally small volume of its battery significantly reduce, according to experts, the possibility of using a Hall sensor.

How the Hall Sensor works [video]

When considering what a Hall Sensor is in your phone, it is worth noting that this element due to the small size of smartphones and other limiting capabilities, it cannot fully realize its inherently rich potential. However, the presence of this sensor in a mobile device makes it possible to make the smartphone more ergonomic and user-friendly - it is convenient to use magnetic cases, conveniently navigate the terrain, and even work with virtual reality glasses. Everything mentioned above allows us to conclude that the introduction of a Hall sensor into modern mobile devices is a useful innovation that will justify itself more than once in the future.

In contact with

The operation of such a sensor is based on the Hall effect. It is as follows: if the semiconductor along which flows electricity, placed in a magnetic field, a transverse potential difference (voltage) will appear. This voltage is called Hall voltage. It can vary from tens of microvolts to hundreds of millivolts. At the time of the discovery of the Hall effect, it had no industrial application. Only 75 years later, thin semiconductor films were invented that had the desired properties. With their help, the Hall sensor was created.

The first such sensor consisted of permanent magnet, rotor blades, magnetic cores, microcircuits and two terminals. He had a lot of advantages. It was very easy to operate. When a signal is applied to its inputs, a time constant square pulse, without sudden jumps. This sensor had small dimensions (on the order of a micrometer). Like any microcircuit, it had its drawbacks: sensitivity to changes in the electric field and too high a price.

Hall sensors are either analog or digital. The former are used to convert magnetic field induction into voltage. Digital ones determine the presence or absence of a field in a given area. If the field induction reaches a certain value, the output of the sensor will be a logical one; if it does not reach a certain value, the output will be a logical zero. Both analog and digital sensors detect the transverse potential difference that occurs when a magnetic field is applied to a current-carrying semiconductor.

Application of Hall sensors

Initially, the Hall sensor began to be used in the automotive industry. It is used to determine the angle of the crankshaft or camshaft. In older vehicles, it is used to signal when a spark has formed.

Hall sensors are widely used in the production of ammeters, capable of detecting current from 250 mA to thousands of amperes. Using sensors, you can measure the force of constant and alternating current high frequency. In this case, it will be proportional to the magnetic field induction, which is induced by the current passing through the conductor.

Hall sensors are used in the manufacture of electromechanical drives, special systems to ensure the operation of actuators in factories and factories. In this case, the sensors will regulate the correct position of the mechanism.

Most Android phones have built-in sensors that measure motion, orientation, and various environmental conditions. These sensors will help monitor the three-dimensional movement of the device or positioning, or changes in the environment. For example, a weather app uses your phone's temperature sensor and humidity sensor to calculate the saturation point. Likewise, your app will use the travel geomagnetic field sensor and accelerometer to find a specific destination. Various sensors Android devices provide precise and accurate data to other applications or directly to you.

If you think that your sensors Android phone are not working as they should, you can always check if it really works fine or not. So how do you determine exactly what's wrong with your phone's sensors?

Whatever the problem, there are apps that can help you figure out the problem and solve it. Even if you don't have a specific problem, it may still be good to go through a small registration on your phone to ensure the health of the phone. Please note that your device may or may not support all of the sensors mentioned above. This article will list some of the most popular apps available for free to test the sensors in your mobile phone. Most of these applications include brief instructions to perform a test for each sensor test.

The Android platform supports the following three broad categories of sensors:

Motion sensors

The force motion sensor measures acceleration and rotational forces. Such sensors include accelerometers, gravity sensors, gyroscopes and rotational vector sensors.

Environmental sensors

The environmental sensor measures various environmental parameters. Examples of environmental sensors are barometers, photometric and thermometers.

Position sensors

A position sensor measures the physical position of a device. Orientation sensors and magnetometers are examples of position sensors.

Now, before we continue, let's take a quick look at some of the main sensors, what they do, and what to do to test these sensors. Later we'll tell you about apps that can automatically run sensor tests.

gyroscope sensor

The gyroscope is used to measure 6 directions simultaneously. This allows the device screen to rotate from portrait to landscape. You can tilt your phone slowly to check if the gyroscope sensor is working.

Accelerometer Sensor

The accelerometer detects the orientation of the phone and measures the acceleration due to gravity, including in three axes. You can rotate the phone slowly to check if the accelerometer sensor is working.

Light sensor

The light sensor automatically adjusts the screen brightness according to the light intensity of your surroundings. You can test the sensor in a dark place and then by moving the phone to an area with bright light. If the screen light changes, it means the sensor is working.

orientation sensor

The orientation sensor detects the directional state of your Android device. It checks for automatic screen rotation. Rotate your phone to check if the sensor is working properly.

Proximity sensor

The proximity sensor measures the distance of an object from the front of the phone. For example, your phone's screen turns off when you hold it closer to your ears during an active call.

temperature sensor

The temperature sensor checks the battery temperature of your Android device. If you surf the Internet using 3G or play HD games you will experience a rise in battery temperature to the point where it becomes quite hot to the touch.

sound sensor

The sound sensor detects the intensity of sound around you and gives you detailed information about changes in intensity.

Magnetic field sensor

The magnetic sensor measures the magnetic fields along the three axes of the phone. It is mainly used to determine direction. Examples include Google app and the Compass app. Just move with your phone to check the magnetic sensor.

Pressure meter

The pressure sensor measures atmospheric pressure. It is used for weather forecasting and for measuring ambient temperature.

CPU-Z

The CPU-Z application collects all the necessary information about the phone and presents it in one window. For each option tab, the corresponding details are displayed at the top of the window.

SOC tab- displays the system-on-chip (SoC) architecture of your part Android smartphone, as shown in the figure below.

Device tab- Displays device details like model, manufacturer, hardware, screen size, total and used random access memory, total and used memory, etc.

System tab- displays detailed information about your smartphone, such as model, manufacturer, board type, display resolution, on Android versions, installed, etc.

Battery tab- Displays battery charging status, level, power source, status, technology, temperature and voltage, etc.

Thermal tab- displays a list of temperature readings. Since the load on CPU causes your phone to heat up, it is good to check that the temperature does not cross 60°C as this indicates a faulty device. This sensor may not be available on all device models. If it is missing, the tab will not display any values.

Sensors tab- displays the values ​​of sensors supported on the device. You can play with the phone to check if individual sensors are working; for example, tilting the phone to check the gyroscope or moving your palms across the screen to check the proximity sensor, etc. If the CPU-Z readings change in response to your actions, then the sensors are fine and working. If you still feel that the sensors are not functioning properly, then you need to check and compare the values ​​with another similar model or device.

Sensor Kinetics

Sensor Kinetics allows you to view, track and understand the behavior of all the standard sensors installed on your phone. You can change the delay setting or activate or deactivate certain sensors. This application demonstrates the use of each of the sensors available on the phone. This way you can easily check the sensors in your phone. Each sensor is attached to a viewer circuit with raw and processed data. It also includes documentation with easy to understand examples on how to test each of the sensors on your phone.

Sensor test

Testing the Sensor app is designed to detect and test the functionality of each of the sensors that are available on your phone. It displays default sensors and displays real time data and information about each sensor. It also displays the vendor, maximum range, resolution and absorption current for each sensor.

Sensor Box for Android

Sensor Box for Android application is a good looking app with impressive graphical representation. It detects all the sensors that are available on your Android device. The application displays all sensors and a corresponding message appears if the selected sensor is not supported by your phone. This application only detects sensor changes, if any, and displays the values. It may not show the correct temperature, proximity, light and pressure values ​​unless some changes occur.

Phone tester

Phone tester app not only checks the sensors on the phone, but also checks the health of hardware devices, Wi-Fi, telephony, GPS, touch, battery and system information. It also checks ambient temperature, humidity, step detector, heart rate monitor and fingerprint sensor - provided that is supported by your device. A Pro app version is also available which displays Additional information, such as phone memory, processor speed and SD card memory.

AndroSensor

AndroSensor supports all sensors that an Android device may have, but displays real-time sensor details only those supported by your device. Detailed information is displayed in graphical and text format. This app also allows you to save sensor data to a CSV file.

Programs and options Other

Apart from the apps mentioned above, there are many other apps available for free with Google Play Store. All these apps will help you in testing your phone's sensors. Some of the apps that are worth mentioning are Multitool Sensors, Sensor Checker and Advanced Sensor Checker. You can install and try several applications and see if it provides you with the information that you were looking for.

If you are using samsung phone, dial secret code * # 0 * # to perform a phone test without having to install any additional applications. Select the sensor tab from the screen that appears and follow the instructions to check the supported sensors on your phone.

If you have any questions about this topic, please feel free to ask in the comments section. We at TechWelkin and our reader community will try to help you. Thank you for using TechWelkin!

The smartphone you probably carry with you all day knows where you are, how you hold it and how fast you are moving. However, major innovations in the field of sensors for mobile devices are still ahead, and await us in the very near future. Now we are witnessing the emergence of a new era - smartphones that analyze various environmental parameters and constantly record them for use by applications and services in everyday life.

So, what sensors, sensors and other clever micro-measuring devices can be found in modern smartphones?

• Proximity sensor: can use an infrared beam to determine that you have brought the smartphone to your ear for a conversation and gives a command to turn off the screen so that you do not inadvertently touch your ear or cheek touch button on the display during a call.
• Gesture sensor: tracks movements, mainly of the eye or hand, and gives the smartphone pre-programmed commands (for example, scroll through a page in the browser or display the latest notifications).
• Gyroscope: determines the rotation of the smartphone in space along three axes (often works in conjunction with the accelerometer).
• Accelerometer: determines the position of the smartphone in space along three axes (often used in other portable devices).
• Geomagnetic sensor (compass): uses the Earth’s magnetic field for orientation to the cardinal points (actively used in navigation services).
• Temperature/humidity sensor: Measures ambient temperature and air humidity
• Barometer: Thanks to this sensor, the smartphone can measure atmospheric pressure
• Hall Sensor: Thanks to this sensor, the smartphone determines whether the case is closed or open
• Motion Sensor: Detects iPhone movement (used in mobile games and to unlock iPhone).
• Light sensor: Automatically adjusts screen brightness based on ambient light conditions
• Gravity sensor: Typically an accelerometer containing a small weight or tube. Moving the weight helps the smartphone determine whether it is being tilted to the right or left, forward or backward. Works mainly in mobile games.
• Fingerprint's scanner: Used in smartphones (iPhone 5s, Galaxy S5) to identify the user by fingerprint.
• Heart rate sensor: can measure the pulse of the smartphone owner (Galaxy S5)

Here's how many sensors it can contain modern smartphone. Let's say thank you to the hardworking Chinese, thanks to whom the cost of all these sensors does not exceed hundreds of rubles. In the future, we can expect the appearance of new measurement sensors in mobile devices (pedometer? micrometer? thickness gauge?). But even without the introduction of new sensors into smartphones, your faithful mobile device knows enough to transfer collected data via API to operate many applications and services: managing a smart home, geofencing, tracking your health and physical activity, communicating with a smart car and smart watch, and so on. The future is already on the horizon.

Modern Cell phones equipped auxiliary sensors, which are necessary for the correct operation of the device. In addition, they increase its versatility. Some models have a Hall sensor installed in the phone. What it is, why it is needed and how it works is described below.

What is this?

A Hall sensor is a device that detects a magnetic field and its strength. Smartphones use a simplified analogue of the device, which detects only the presence of a magnetic field without reading its strength along the axes.

The operation of the device is based on the Hall effect, discovered in 1879. If a conductor through which an electric current flows is placed in a constant magnetic field, under its influence the electrons are deflected towards one of the faces of the plate. A negative charge accumulates in this part, while a positive charge accumulates on the opposite side. The process continues until the resulting electric field compensates for the magnetic component of the Lorentz force. The resulting potential difference at the edges of the plate is recorded by a Hall sensor.

In smartphones, it is represented by a microcircuit, which at the output creates an information signal in two states:

• one (signal is given);
• zero (no signal).

The mobile phone reads it and, depending on the state of the signal, performs one or another action.

Important! The sensor can be installed next to microcontrollers or logic elements - it does not affect their operation.

You can find out if your gadget has a Hall sensor by reading the instructions for your smartphone, which should indicate this. Or do as shown in the video.

Why is it needed?

This device has a wide range of capabilities depending on the system in which it is used. But it is impossible to fully realize its potential in smartphones for several reasons:

• compact dimensions of a mobile phone;
• reducing battery consumption;
• not necessary.

In smartphones, the Hall sensor is used in two cases:

• in a digital compass and to improve geopositioning, providing a quick “cold” start of the GPS navigator;
• interaction with a magnetic smartphone case.

The principle of interaction with a magnetic case

Magnetic cases lock/unlock the gadget's screen when the protective cover is closed/opened. This function is provided by a Hall sensor built into the device: it reacts to the approach/removal of the magnet on the flip, as a result of which the magnetic field changes. This is registered by a sensor, which gives the smartphone a command to unlock/lock the screen.

Some cases have a window to display a certain area of ​​the screen, where you can see the clock, messages, missed calls, etc. This effect is also provided by a Hall sensor, which determines whether the screen should be completely blocked or part of it should be left active.

At the same time, the magnet itself, built into the flip case, does not harm the smartphone, as is clearly shown in the video.