Qi standard chargers are supported. Qi wireless charging standard

• 1. What is Qi wireless charging

  The world is becoming mobile and "wireless".

  AT modern world all manipulations with file transfer using a smartphone happens "over the air". Internet access via wi-fi - at home, at work, in a cafe is taken for granted, and rarely anyone has difficulty using it. The time has come forwireless transmission energy.

  In 2008 was founded " Wireless Electromagnetic Energy Consortium" (Wireless Power Consortium, WPC), which brought together manufacturers from Europe, Asia and America. The goal of the "Consortium" is to develop a single standard for wireless charging technology.

  Already in 2009 the company Palm provided the first phone to support wireless charging. Later, in September 2012, Nokia introduced 2 smartphones to the market - Lumia 820 and Lumia 920 also with qi standard support. Next, major smartphone manufacturers pulled up - Samsungg, Google Nexus(Asus, LG), Sony, etc.

  Since 2014, our company Zaryadqi has been developing and distributing wireless chargers in Russia. Our store has the largest selection of wireless chargers and we are constantly monitoring new products and expanding our range. You will definitely find the right charger for you in our store.

• 2. Working principle

  In plain language:

  • The charger is connected to a power source.
  • A magnetic field is created.
  • Smartphone must support wireless charging- have a built-in receiver or a receiver installed additionally.
  • The phone is placed on the charger.
  • Smartphone charging starts automatically.

  From a technical point of view:

  Energy is transferred from the transmitter to the receiver-receiver through an interconnected magnetic field generated by the flow of alternating current through the transmitter coil.
  If the receiver coil is in close proximity, a significant portion of the transmitter lines of force will pass through the receiver coil, creating alternating current in the receiver, which is then converted to a constant voltage.

• 3. Benefits

  Just. Put your smartphone on the Qi wireless charger and it will start charging automatically.

  Modern. All major IT companies are already developing their devices according to the Qi standard.

  Universal. Any device with a Qi receiver-receiver is charged by any Qi wireless charger.

  Safely. The generated electric field is safe for humans and extends only 1 cm from the device.

  Comfortable and convenient. There is no need for a bunch of wires that later get tangled or simply lost.

• 4. Phone models that have a built-in receiver-receiver and support wireless charging out of the box

  More and more smartphone manufacturers are starting to build receivers into their phones. top models: Apple iPhone XS, XS MAX, XR, X etc, samsung galaxy S9/S9+/Note 9, Xiaomi Mi Mix 2S, Huawei Mate 20 Pro and etc.

  • Apple iPhone 11 pro Max
  • Apple iPhone 11 pro
  • Apple iPhone 11
  • asus padfone s

  blackberry

  • Blackberry Private
  • Blackberry Z30
  • Blackberry Classic
  • Blackberry Passport
  • Blackberry 8900
  • Casio g "z one commando

  Caterpillar

  • Cat S50
  • Cat S50C
  • Dewalt md501
  • Dewaltmil810g

  Energy System

  • Energy Phone Pro Qi
  • Fujitsu Arrows F-09D
  • Fujitsu Arrows Kiss F-03D
  • Fujitsu Arrows Kiss F-03E
  • Fujitsu Arrows X F-10D
  • ZTE Telstra Tough Max
• 5. For some phone models, special receivers are available to support wireless charging
• 6. How to use wireless charging

  

• 7. Types of wireless chargers

  We conditionally divide wireless chargers into several types according to functionality:

  • . Standard charging stations in the form of a small "platform" on which the phone is placed, or charging built into the equipment - a lamp, clock, weather station, etc.
  • . Wireless charging for use in the car: with special holders and brackets for the phone and adapters for the cigarette lighter.
  • . Wireless chargers with stand function, i.e. The phone is at an angle during charging for easy viewing of video, mail, social networks.
  • . Wireless chargers with a built-in battery differ among themselves, in addition to design, in the number of additional usb ports and battery capacity - from 4000 mAh to 10000 mAh.
  • . Wireless chargers for embedding in tables, cabinets, bar counters. They have a special design and protection against moisture and dust.

  And also by scope or place of use:

  • Home / office
  • In the car
  • On the road
• 8. There are receivers
  • Embedded- already installed in the smartphone by the manufacturer.

  If the manufacturer of your phone has not provided for the possibility of wireless charging, it can be easily adapted to this charging! For this, a special receiver film is used - there are several types of them:

  • In the form that is installed under the cover of the smartphone. To do this, the phone must have special contacts.
  • , which connects to the lighting power port on Apple and micro-usb on Android smartphones.

  Image	Description
  	The film is attached under the cover of the phone, the functionality of the phone is not reduced. The standard cable can be used at the same time as the receiver film is installed. Such receiverqifor phones with special contacts suitable for phones that have special contacts for wireless charging: Samsung Note 4, Samsung Note 3, Samsung Note 2, Samsung Galaxy S5, Samsung Galaxy S4, Samsung Galaxy S3 and more.
  	The film is attached to the back of the phone. At the same time, it can be closed with any standard cover: made of leather, plastic, silicone - this will not affect the charging process. The connector, which is inextricably linked with the film, must be in the Lightning connector for Qi charging. The presence of a film receiver does not cause inconvenience. Such Apple-receiverqi suitable for Apple devices with Lightning connector: Apple iPhone 5, 5s, 5c, 6, 6s, 6Plus, 6SPlus, SE, 7, 7 Plus; iPad Air 2, iPad mini and others (Apple in this moment does not support wireless charging without accessories)
  	Such universal receiverqi Suitable for any phone equipped with a USB connector for classic wired charging. The film is attached under the cover or case of the smartphone. The plug, inextricably linked with the film, for charging according to the Qi standard must be in the Micro-usb connector. The presence of a film receiver does not cause inconvenience.

  On phones with a Micro-USB port, the connector can be one of three types, depending on its appearance, when you put the phone on top of the screen.

  Connector type "C" appeared relatively recently - it can be found on a few devices. So, type "C" is equipped with MacBook 12", Samsung TabPro S, Google Nexus 6P, Microsoft Lumia 950 XL, ZUK Z1, Google Pixel C, Google Nexus 5X, One Plus 2, Acer Aspire Switch 10 V and more.

  In addition to the above receivers, depending on the location of the connector in the phone, such film receivers may be suitable - they are called lateral or offset:

  

  Accordingly, each type and position of the connector needs its own Universal receiverqi. By identifying the correct type of Micro-USB connector in your phone, you will buy the right receiver for wireless charging and allow yourself to forego wires!

  • There are also: the receiver is already built into the case, so just put the case on your phone and it will be able to charge wirelessly.

  

  You can always tell the manager of the online store your phone model - we will select the best receiver for you!

• 9. Difference between wired and wireless charging

  Wireless charging produces a current of 1 ampere and a voltage of 5 volts. Standard adapter the power supply that comes with the smartphone gives out from 1 to 2A. And when charging the phone from a computer (USB port), the phone is charged with a current of 0.5A (USB 2.0) to 0.9A (USB 3.0).

  In this regard, you will not even feel the difference in charging time, or it will not be significant.

• 9. Energy efficiency

  The energy efficiency of Qi wireless chargers is approximately 80%. It should be understood that it is simply impossible to achieve 100% energy efficiency; for standard wired chargers, this figure ranges from 75% to 95% at best.

• 10. Security

  Wireless chargers use non-ionizing frequencies that have no harmful physiological effects on humans. The Qi 1.2 standard includes the detection of foreign objects in the field of action of the charger, providing additional security use; Charging is only possible with Qi-compatible devices. Also our charging device and smartphones have built-in safety mechanisms based on thermal control.

Do you have any questions?

Qi is the global international standard for wireless charging of a variety of devices. The standard is being developed by the Wireless Power Consortium (WPC). The name Qi (read Qi) is based on the pronunciation of one of the most important Chinese characters. Qi is the fundamental basis of Chinese philosophy, most accurately translated as vital energy. It is well known that electrical energy can be transmitted without the use of conductive elements. Qi is based on one of the methods of wireless transmission of electricity over a distance - the method of induction transmission. This method was known to mankind in the XIX century. Most often, its implementation can be found in the production of most electrical transformers.

The essence of this method is as follows: an alternating electric current passing through the primary winding of the transformer, due to the phenomenon of electrodynamic induction, creates an alternating magnetic field acting on the secondary winding. This field induces an electric current in the secondary winding. At the same time, the closer the primary and secondary windings are located, the higher the efficiency of electric current transmission. As one winding moves away from the other, more and more of the magnetic field is wasted, not transferring energy. This property determines the main disadvantage of this method - a small distance of its action.

The Qi standard is primarily aimed at domestic use of wireless chargers, in which there is no need for a large distance between the receiver and transmitter of electricity. But there is a need for the consumer to get rid of uncomfortable charging cables, contact stands and other devices. The recommended distance between the charging platform and the device to be charged in this case should not exceed 4 cm.

Such schemes have long been widely used in the designs of electric toothbrushes, induction cookers, and are now being actively introduced in the mobile phone market. Today, all the leading manufacturers of cellular technology have included the ability to charge their phones using the Qi standard. To activate the process of recharging the battery of the phone, it is enough just to put it on a special compact charging pad, the pad, in turn, must be connected to a power source (to a regular household outlet).

In Qi, the high efficiency of wireless power transmission is achieved by applying the resonance effect. The transmitter and receiver are tuned to the same frequency. This is done by including capacitors in a flat spiral or a single-layer solenoid, which is a transmitting coil located in the charging pad. In this case, the transmission efficiency is 80%. For comparison, the efficiency when charging a phone in a traditional wired way is from 75% to 95%, and 100% efficiency is simply impossible to achieve!

In cell phones that support Qi technology, the receiving coil - the receiver is made in the form of a very thin copper spiral, attached to the back cover of the phone from the inside. The thickness of such a receiver is negligible and the installation does not cause great difficulties, so it is possible to place it under a standard cover without additional investment. As an alternative to this option, it is possible to replace the standard phone cover with a new one with an already built-in receiver.

WPC-certified Qi-certified chargers and gadgets do not use ionizing frequencies, and therefore cannot have harmful physiological effects on humans or animals. Also, most modern chargers and smartphones have built-in protection mechanisms based on thermal control. They are also able to detect the presence of foreign objects in their field of action, which also provides additional safety of use.

If the mobile phone and the charger support the QI standard, they will recognize each other as soon as they touch. After the exchange of the necessary information, the process of energy transfer begins: the transmitter coil generates a magnetic field, through which energy is transmitted inductively to the receiver.

1. The "charger" transmitter first detects the presence of a QI-enabled device that needs to be powered. It then generates an alternating current in the transformer. A magnetic field is generated in the coil, through which energy is transferred inductively to the device to be charged.

2. Communication The controllers of both devices "agree" on the terms of the transfer of energy (Power Transfer Contract), thereby ensuring uninterrupted and efficient charging of the device. Data exchange is carried out by means of phase modulation of the magnetic field.

3. Receiver In order to store the alternating current generated by induction in the battery, the receiver needs to convert it to direct current and change the voltage accordingly. Finally, the receiver controller signals that the battery is fully charged and the charger stops the process.

Another important feature of the Qi standard, which is undoubtedly worth mentioning, is the presence of a data exchange interface between the charger and the smartphone. The exchange takes place at a speed of 2 kbps and allows you to transmit and receive information about the remaining charge level of the battery, test it and, upon completion of charging, turn off the transmitting device without consuming excess electricity and without damaging the battery by overcharging it.

Today, the development of Qi can only be compared with Wi-Fi, the common global standard for wireless data transmission. Now, almost wherever you are, you can access the Internet through a point WiFi access. All mobile devices - smartphones, tablets, laptops are equipped with Wi-Fi modules. And it's no secret to anyone that it is wireless technologies that are our future, which has already practically arrived.

The next step, designed to make our lives easier, is the massive use of wireless universal chargers. To solve this problem, the Wireless Power Consortium community has developed the international Qi standard.

The Wireless Power Consortium brings together more than 140 organizations that develop equipment and devices. The idea of ​​Qi is simple: any device with the Qi logo can be charged by any charger with the same logo. No more unique wired chargers for specific devices, no more hassle with cables, and no more hassle with travel adapters. Qi is an international standard, which means your device can be charged without wired charging, over the air, wherever you are. You just have to find the nearest place equipped with charging surfaces. There are more and more such charging stations around the world. Soon, wherever there is Wi-Fi, there will be Qi! You can charge in offices, hotels, airports, cafes and restaurants. In the near future, one of the main criteria for choosing a new gadget by the buyer will be the presence of the Qi logo on it. Already now such monsters of the market as Samsung, Apple, Sony, Ericsson, LG, HTC and Motorola use Qi technology in their devices. In this case, the device may already contain a receiver for wireless charging (Qi-solution), or it may be understaffed with it (Qi-ready).

The number of Qi-enabled smartphones already on the market is more than 100 different models, and the number of their sales has already exceeded 8,500,000 units. The most popular among them are Samsung's flagship Galaxy models, iPhone phones from Apple, Nokia's cutting-edge Lumia line.

Even Toyota in its latest model Avalon Limited installed an integrated Qi charging pad. A special panel is placed next to the driver on the center console, putting the phone on it will start charging it. Thanks to the efforts of the Wireless Power Consortium, the wireless charger ecosystem is also growing very fast. Many network leaders, such as Virgin Atlantic and The Coffee Bean & Tea Leaf, have entered into agreements to equip tables for visitors to their cafes with Qi-surfaces for charging gadgets. In the near future, the number of places where you can charge your personal device wirelessly will increase many times over. And you can charge your smartphone wirelessly at home or in your car right now, all you need to do is purchase a Qi-certified charging pad from us.

The prospects for the development of the Qi wireless charging system depend on the speed of the spread of this standard in the world and on the support of its market leaders. In fact, its distribution is already becoming ubiquitous. All the world's industry and industry leaders have already included it in their devices. It is also worth noting the lack of competition in this market. The presence of one common standard for all suits everyone. Moreover, in fact, all other interfaces have already been made wireless. And if nothing needs to be connected to the device, then it can be made completely or partially sealed. With such a smartphone, it will be possible to communicate even under water. And what today is perceived with humor tomorrow will become a public everyday reality.

Wireless charging technologies electronic devices developed by manufacturers for a very long time. Perhaps the most familiar popular variant of their real use can be considered some models of electric toothbrushes. In this case, the advantage of this solution, in addition to the convenience of charging, is the absence of external electrical contacts, which are not very practical in a bathroom. It is also worth paying attention to the regular operation scenario of this device and the absence of the need to charge the brush in other places.

However, the smartphone market has not yet seen a wide distribution of similar solutions that look very convenient. There are several reasons for this, in our opinion. The first two are quite typical for most new technologies: an increase in cost and a small number of available "reciprocal" parts" - the wireless chargers themselves. But more important reason is a significant change in the mobile device charging scenario. When using a cable, you lose only one thing - the ability to move your smartphone over a long distance. And in most cases, this is not very significant (besides, you can just use a long cable). However, you can continue to use telephone conversations, Internet, mail, multimedia and all other applications. With wireless charging, this cannot be afforded. It without fail requires finding a smartphone on a special stand while charging. Although, of course, one can imagine a variant with speakerphone or headset.

It turns out that actually wireless chargers can only be of interest in a limited number of scenarios - for example, in a charging dock at night or when navigating in a car. For frequent everyday or emergency use today, they are not very convenient. However, the option of chargers in a cafe that is already being tested can also be useful. Over the past few years, smartphones have received bright screens high resolution with a large diagonal and powerful multi-core processors, however, time active work from one charge of the rechargeable battery practically did not change. If they were guaranteed to last more than a day, the situation would be different - it would be enough for the user to use the wireless charger at home, putting the smartphone on it for the night. It should also be noted that for such popular devices like tablets, the use of wireless charging is less likely. In particular, they require more high power power supply than smartphones, and besides, the stand will be too large. (By the way, it should be noted that during testing, we met with the fact that in some combinations, a certain fixed position of the smartphone on the stand is required for operation.) The use of wireless charging with headsets or other accessories is also unlikely, the reason for the absence of such solutions will be the impossibility of using sufficiently large receivers coils in these devices.

In general, the following advantages of a wireless solution can be noted:

• no mechanical/direct contact;
• possibility of use in an unfavorable environment;
• ease of use (in some cases).

However, there are also disadvantages:

• less efficiency;
• long-term charging;
• increase in the cost, weight and size of the smartphone;
• the inability to fully use the smartphone while charging.

But it must be admitted that certain shifts have been outlined in this area lately. Not every manufacturer, even the largest, has the strength to create a truly universal solution. We can assume that the beginning of standardization was laid in 2008 with the creation of . The version they developed called Qi is today the only solution recognized by a large number of market players. In total, according to the consortium, at the time of writing, almost 200 companies were represented in it, and more than 350 products were present on the market with support for this standard. Qi can be found in products from HTC, LG, Motorola, Nokia, Philips, Samsung and other manufacturers.

Another organization in this area is formed in 2012. Qualcomm, which is part of it, is currently offering its implementation of a technology called WiPower.

It is also worth mentioning, created in 2012, which also sets itself the task of developing and promoting the industry standard for wireless charging. Following him, in October of this year, was organized working group.

At the moment, you can find Duracell Powermat products on the market, but they are not widespread and are not used by smartphone manufacturers, so we will consider Qi solutions later in this material.

From a technical standpoint, a wireless charger uses an electromagnetic field to transfer power from one device to another. If we talk about the current implementation of Qi, then here in the low power section the following characteristics are set: a distance of about 5 mm, a maximum power of 5 watts. Recall that a power of five watts corresponds to the most common wired chargers with a USB interface and a current of 1 A. In addition to the coils themselves, special controllers are involved in the process that monitor the supply and reception of energy, and the control unit is installed in the mobile device.

Below we consider three solutions to this standard. different manufacturers in terms of usability, charging speed and compatibility.

Nokia

To enable wireless charging of its devices, Nokia offers two accessories: Nokia Wireless Charging Plate (DT-900) and Nokia Wireless Charging Pillow by Fatboy (DT-901). They differ only in design: the first is a strict device made of plastic, and the second is a soft and flexible "pillow". Both models are available in several vibrant colors to match the range. Nokia Lumia. Other characteristics are the same: support for the Qi standard, outdoor unit power supply 12 V 0.74 A with a cable 1.8 m long.

In testing, we used the DT-900. The body of the stand is made of plastic, in our case - bright red. Its dimensions are relatively small - about 120 × 60 × 11 mm.

The upper matte surface has the manufacturer's logo in the center, around which there is a low rubber rim. It allows you to keep your smartphone on the charger. Note that the large dimensions of the panel roughly correspond to a smartphone with a screen diagonal of 4.5″. So modern large devices will close it completely.

The edge and bottom surface are made glossy. On one of the short rounded ends there is a power supply input, and on the opposite side there is a white charging indicator. At the bottom of the panel is a rubber insert that prevents slipping.

The complete cable is red, but the power supply itself is white. It is worth paying attention to the parameters of this unit - it gives out 12 V 0.75 A, which is significantly more than standard wired chargers give out. In particular, the regular AC-16 is designed for 5 V 1 A. It can be seen that the power loss is significant.

The list of compatible devices includes models from Lumia 720 and above. However, only the Lumia 920 has a built-in receiver, for the rest you will need to purchase an additional back cover, which communicates with the device through the contacts located on the back of the smartphone case. In particular, when working with the Lumia 1020, the lid increases the weight by 30 g, and the thickness by about 2 mm. Perhaps this solution is more interesting than the built-in module in the Lumia 920. At least until such technologies are used everywhere.

In operation, the device turned out to be quite convenient. Its small size allows you to freely place it on a table, bedside table or shelf. The built-in indicator glows during charging, which starts just a couple of seconds after placing the smartphone on the stand. Note that if you use large smartphones, this indicator may not be very visible. It is also worth paying attention to the non-standard power supply and connector. Other models discussed in this article can be "transformed" into regular chargers and used with most smartphones by simply unplugging the Micro-USB cable from the cradle.

We carried out the first charging test together with Nokia Lumia 920. The test showed that the wireless charger is able to work even with a completely discharged device, which, of course, should be considered a plus of the solution. As for time full recovery charge, then with the DT-900 it turned out to be almost the same as with a regular wired power supply - about two and a half hours. So the charging speed in this case can be considered high, but the main thing is that it will be convenient for the user to predict the required time, since it does not depend on the option used.

Compatibility testing with a Samsung Galaxy S4 equipped with a branded wireless charging cover was successful. The smartphone was able to fully restore the charge in about 3 hours and 10 minutes. It is also possible to start work with a completely discharged battery.

Note that Nokia has an unusual model in its arsenal. external battery with wireless charging - Nokia Portable Wireless Charging Plate (DC-50). The cost of Nokia DT-900 at the time of this writing was about 2600 rubles. Branded covers with receiving modules were offered for 1000-2000 rubles, depending on the model.

Samsung

Samsung has chosen a slightly different approach to packaging. Her S Charger Kit includes a charging cradle and a new smartphone cover with built-in charging circuits.

When used with the Samsung Galaxy S4, it increases the weight of the device by 20 g, and the thickness by about 2 mm. It is interesting that the currents are indicated on the components: 5 V 2 A is required at the input (this is how much a standard unit from this smartphone gives out), and only 5 V 0.65 A can be obtained at the output.

The body of the stand is made of plastic. Its dimensions are about 161×91×12 mm. For top panel used gray semi-gloss material. Its concave shape helps keep the smartphone in the right position. The manufacturer's logo is visible in the center. However, if we talk specifically about the Galaxy S4, then it is noticeably smaller than the stand - the dotted line just corresponds to the size of the smartphone.

The main body is glossy white. In the center of one of the short ends is a Micro-USB jack. Away from it, on the top edge, there is a green LED that lights up when the smartphone is placed on the stand and charging starts. The place for the indicator is not chosen very well - it would be more convenient to see it on the opposite side. However, due to the large size of the stand, this is not very significant. Most of the bottom is made of rubber, which allows the stand to hold firmly on the table.

Full charge time for Samsung Galaxy S4 is about three and a half hours. Checking the operation using a 1 A power supply showed that in fact the requirement of a two-ampere model is not justified, a less powerful unit will be quite enough. This replacement does not affect the duration of wireless charging. Note that this configuration is also capable of restoring a completely discharged smartphone.

Recall that when using the bundled wired charger, the charge recovery time is about two and a half hours. At the same time, up to 90%, the charging speed is quite high, but in the last ten percent it decreases.

In domestic stores, this kit is offered for about 3,000 rubles.

Power Qi

The presence of the standard allows the release of compatible devices to different companies, and not just smartphone manufacturers. In particular, we were able to find an almost “unnamed” version of the PowerQI T-100 wireless charger for testing.

The package includes a stand, a power supply (5 V 1.5 A) with a Micro-USB cable and a special receiver unit. The last element is usually individual for each smartphone model, in our case it was an antenna and a control unit for the Samsung Galaxy S4. In terms of cost on foreign trading floors, approximate guidelines are $35 for a charger with a power supply and $10 for a receiver unit.

The stand is made of white glossy plastic and measures 150×80×10 mm. flat top part It has slightly bevelled edges and lacks any rubberized elements, so the smartphone does not hold in place very well. The gray paint panel has the name of the company and model, as well as the logo of the wireless charging standard. The stand rests on four rubber feet.

The LED lights up green when there is external power, and when the smartphone is placed for charging, it changes color to blue. We also note the supply sound signal at this moment, which allows you to be sure of the identification of the device and the start of charging.

The receiver unit is a flat antenna and a small controller board manufactured by Texas Instruments. It is supposed to be installed under the standard smartphone cover with connection to the contact pads present on the case.

Note that the output current is indicated on the receiver - 600 mA. For smartphones that do not have this capability, there are options in the form of covers with a connection via a standard Micro-USB. Interestingly, this antenna seems to be a little smaller in size than in a standard Samsung accessory; this may result in the need for more accurate positioning of the smartphone on the transmitter. In our testing, this situation arose with the Nokia charger due to its compact size.

The charging time of a smartphone with a branded cover on a PowerQi stand is approximately 3 hours and 30 minutes, so in terms of transmitters, these models turned out to be the same. Other combinations of receiver and transmitter give similar results, including the ability to restore the charge of a smartphone with a completely discharged battery.

Conclusion

Many companies are now showing interest in wireless charging technologies for smartphone batteries. However, no revolutions should be expected here. There are many players on the market, it is difficult for them to agree among themselves, in addition, the familiar “chicken and egg” problem is superimposed. So today it is probably not worth considering the presence of a built-in or optional wireless charging module as a must for top-end devices.

In this article, we looked at several solutions developed according to the Qi standard. They showed good compatibility and were generally quite efficient. Some concern is caused only by the relatively low possible power in this modification of Qi, which does not allow to provide fast recovery charge modern devices with high capacity batteries. However, if we consider these solutions as a night charger, they will be quite enough for most smartphones. As for active work scenarios, for example, navigation in a car, it is quite possible that a wireless docking station will not be able to restore battery power while running resource-intensive applications, but will only act as an additional power source, reducing the discharge rate of a standard battery .

In any case, Qi technology can be considered quite mature and suitable for use not only by enthusiasts, but also by ordinary users who find this scenario useful for themselves. Moreover, it is not at all necessary to use original accessories - solutions from lesser-known companies offered on Internet sites at a relatively low cost may also be suitable.

Today, it is already hard for us to imagine our life without mobile gadgets. This has led to the fact that a huge amount of wires accumulate near household outlets, among which it is not so easy to find the necessary “charging”. In this case, a wireless charger will help solve the problem. The principle of its operation is very simple - just place the gadget on a special panel to charge it. The accessory is based on the principle of operation of the induction coil. This technology is called Qi. It has become very popular lately. In 2015, the globally popular brand began selling furniture that will have a built-in wireless charging module. Today, all flagship smartphones support Qi. It is expected that soon transmitters or, in other words, modules can be found at airports, restaurants, cinemas, fast food, shopping centers, which will allow charging phones and tablets at any time. In fact, this will make life easier for users of mobile gadgets. We are entering new era, where it is not necessary to carry around with you everywhere for all the devices that we use.

The wireless power standard is called Qi. In Russian, the word is pronounced as "Qi". The standard bears such a name in honor of the term of Eastern philosophy. It is developed by the WPC Wireless Electromagnetic Energy Consortium. This organization brings together global electronics manufacturers and sets itself an important task - to standardize the process of charging gadgets using the induction method.

In the near future, all devices can be charged without being connected to the network. It's incredibly convenient. Each of us at least once faced with a situation where. We urgently need to find a way out. Soon, wireless charging modules will appear in all public places, as well as at every user's home. At home, you can simply place the module in a convenient place, and it will never get lost, unlike wired "charging". It is enough just to place a gadget on it and wait a bit until the battery capacity is replenished.

The principle of operation of wireless "charging" is based on the properties of an induction coil to transmit electric current. In the school physics course, we were taught that when an induction coil is connected to a power source, a magnetic field arises in it, perpendicular to the turns of the coil. Thus, if you place two coils within the range of the magnetic field and at the same time connect one of them to a power source, then voltage will appear in the second coil. In this case, it is important to take into account the fact that two induction coils should in no case be in contact with each other. Such a simple principle lies in the operation of wireless chargers that support Qi technology.

There are two varieties of the Qi standard. The first involves charging at low power - 5 watts, and the second - at high power - 120 watts. Qi high power is not currently produced by manufacturers due to objective factors. With Qi at 120 watts, you can charge your laptop. Qi at 5 watts is used to replenish the capacity and phones. It should be noted that different current strengths are required for a tablet and a smartphone. A wireless charger for a phone creates a current of 1 amp, and for a tablet computer - 2 amps. When choosing an accessory, be sure to pay attention to such characteristics.

Qi Energy Efficiency

A modern wireless charger consists of two components. One of them is built directly into a gadget that supports Qi and is called a wireless charging receiver. In fact, it is a receiver that conducts electrical current to the battery. The second component is called the transmitter. If the purchase of wireless “charging” is meant, we are talking about the transmitter. They come in a variety of shapes and sizes. The most common are round and rectangular transmitters.

To better understand how wireless charging works, it should be noted that the magnetic field is capable of transmitting not only electric current, but also data on bytes and bits, which was taken into account by the developers of the Qi standard. The interaction between the coils will only occur when the gadget with the built-in transmitter is close to the transmitter.

If the accessory for charging the gadget works in the background, then the pulse sent every 0.4 seconds by the transmitter will not change the voltage in the coil built into the transmitter. We can conclude that a modern accessory can recognize in which mode to function. As soon as a smartphone is nearby at a distance of several centimeters, the voltage in the induction coil will drop sharply, and the device will switch to active mode. As soon as the smartphone battery is charged, the corresponding signal will switch the charger to background mode. It can be concluded that modern wireless accessories for battery replenishment are energy efficient.

Is Qi technology secure?

Some users mistakenly believe that the Qi wireless charging function can be harmful to health. The fact is that magnetic radiation is not ionizing. In its effect on the body, it is similar to a signal mobile communications, radio signal. At the same time, the signal mobile network, which comes from the tower, is stronger and has a continuous character, while electromagnetic radiation disappears immediately after charging the smartphone battery.

The power of wireless chargers is 5 watts. It is not enough to have an effect on the human body. We can talk about a negative impact only if the power of such devices is 120 watts. But such models are not produced on an industrial scale. This explains the lack of wireless chargers for laptops. It is important to know that wireless battery charging technology has long been used in many models of electric shavers and electric toothbrushes, which once again proves its safety.

Which smartphones support wireless charging?

First of all, we want to note that not all gadgets today support the wireless charge function. Apple intentionally places products on the market that are not compatible with Qi. In this case, we recommend purchasing a special case with a built-in telecoil.

Flagship devices basically always support Qi technology. These include such popular models smartphones like Samsung Galaxy S6, Sony Xperia Z4v, Samsung Galaxy S6 Active, Google Nexus 6, Motorola Droid Turbo, Nokia Lumia 930, Samsung Galaxy S6 Edge. Already, dozens of models from various manufacturers can be charged using a wireless accessory, which provides maximum convenience for users.

Can you make your own wireless charger?

Wireless chargers are quite expensive, given that they are a conventional induction coil. The question arises: "How to make a module with your own hands?". In principle, if you have knowledge of the basics of physics and special equipment for measuring force and power electric current, it won't be a big problem. Fans of radio electronics are able to assemble and not so simple devices, but ordinary users we do not recommend such experiments.

On aliexpress.com, you can find separately wireless device receivers for some smartphone models, including the Google Nexus line. It's easy enough to install on your phone. Under the cover of the device there are two contacts, which provide for a positive and negative pole. It is enough to buy and connect the receiver, after which you can conduct a wireless charging test. This solution is optimal if you somehow got a wireless charger, for example, you were presented with a gift, and your gadget model does not yet support the Qi function.

Wireless battery charging technology is gaining more and more popularity in the modern world. In the future, in many public places it will be possible to replenish the battery capacity. It is expected that stadiums, parks, restaurants, cinemas, fast foods will be equipped with wireless chargers. When buying smartphones, we recommend paying attention to the support for the Qi function, which is present in all flagship models in 2015.

Qi is the Chinese word for "energy flow" (pronounced "chi" in English) and the universal standard for rechargeable batteries such as iPods, cell phones and cameras.

The power transmission takes place due to the fact that the receiver receives energy not through a traditional cable, but in a non-contact way, thanks to the use of electromagnetic fields. The principle is very simple: the Qi transmitter, which is the base station, directs the necessary energy to the receiver.

Technology Description

The Qi wireless charging standard is based on magnetic induction between the flat coils of the transmitting and receiving apparatus. Primary and secondary windings form two parts of the coreless charger circuit is shielded on the lower surface of the primary and upper - secondary coil. This, and the close proximity, guarantee acceptable power transfer efficiency. In addition, it minimizes the impact of the magnetic field on users.

Typically, a base station has a flat surface on which one or more mobile devices can be placed. This ensures that the vertical distance between the primary and secondary windings is sufficiently small. In addition, there are two ways to align the windings horizontally.

In the first case, the user independently sets the secondary winding opposite the primary winding on the interface surface using prompts from the mobile device.

The second method, called free positioning, does not require the active participation of a person. In one implementation, several primary windings are created for this. Another variant uses mechanical means to move the primary coil under the secondary.

Structural elements

The power transmitter consists of two main functional units, namely, a power conversion unit and a communication and control unit. The element of the first, generating a magnetic field, is the primary coil. The second changes the transmit power to the level requested by the receiver. In addition, the base station may contain more than one transmitter to serve several mobile devices, since one primary winding interacts with only one secondary at the same time. And finally system unit provides power and controls multiple transmitters.

The gadget contains an energy receiving unit, which is a secondary winding, and a communication and control unit. The latter regulates the transmitted power to a level acceptable to the subsystem connected to the power output of the receiver. An example of such a subsystem is a battery.

Stages of communication

After activating the communication and control unit of the transmitter, it sends a signal to the receiver to receive a response confirming the presence of a Q-compatible device.

Upon receiving the request, the receiver enters the selection phase. If the offered voltage is high enough, then the ping phase begins.

When receiving a response from the transmitter mobile device sends a signal strength packet and enters the identification and configuration phase, or sends a power transfer complete packet and remains in the ping phase.

Then an identification packet and control packets are sent. The receiver enters the charging phase. At the same time, it controls the transfer of energy by transmitting control packets. base station, which contain information about adjusting the current of the primary winding, about the received energy, about the charging status, about the completion of the transfer.

What is a wireless charging point?

Qi-charging is universal because it ensures the compatibility of mobile phones and different manufacturers. The only condition is that both parts - transmitter and receiver - must comply with the Qi standard.

Thus, any Qi wireless charger will fit any Qi mobile receiver, regardless of brand or model. A bunch of cell phones from various manufacturers, including Samsung, Nokia, LG, Sony, HTC and Motorola, are already Qi-compliant and therefore can be connected to any charging station that meets its requirements. The number of compatible gadgets continues to grow as more and more companies support wireless power technology. This makes it possible to charge battery-powered electronics with a single power source.

How it works?

The mobile charger is not the latest invention. Electric toothbrushes have been using inductive power for many years. The process uses a resonant inductive coupling of the base station transmitter and receiver mobile phone. The primary coil continuously sends a test signal to the sender to check for a change in capacitance or resonance indicating the presence of a compatible phone. The transmitter modulates the charge and checks if the Qi wireless charging standard is supported.

Once compatibility and energy requirements are taken into account, the process of inductive energy transfer begins. In this case, the contact between the receiver and the transmitter is maintained. Once the battery is fully charged, they will go into standby mode. Universal charging is activated and transfers energy only if the connected gadget is on it.

Coils transmitting and receiving energy are specially shielded in order to reduce electromagnetic radiation.

The main features of the technology

• A method of non-contact power transmission from a base station to a mobile device, which is based on the near field magnetic induction that occurs between the coils.
• Transmission of about 5W of power using a suitable secondary coil (having a typical outer dimension of about 40mm).
• Operation at frequencies from 100 to 205 kHz.
• Support for two methods of placement on the surface of the base station:
  • guided positioning, where the user is assisted to correctly position the mobile device in a location providing power through one or more fixed points;
  • arbitrary placement on the surface of the charging station.
• A simple one that lets your phone or tablet take the lead.
• Significant design flexibility to integrate the system into a mobile device.
• Low standby power consumption (depending on implementation).

One for all

How convenient would it be to have one Qi-charger for all phones, players, cameras without a lot of tangled cables?

While countless new smartphones are sweeping the world, battery life is getting shorter. And every manufacturer and even every gadget has its own charger. And with each purchase, their number increases. Ultimately, the user is lost in a pile of various power adapters. Thanks to Q-technology, they become unnecessary, and tangled tangles of cables disappear, and this is not all the advantages of this technology.

Just as Wi-Fi became the global standard for wireless Internet connections and Bluetooth eliminated the need to hold your phone in your hand, so Qi is becoming the global standard for inductive charging of battery-powered gadgets.

Is electromagnetic radiation harmful?

Expert opinion is divided. On the one hand, many scientists confirm that a small amount of electromagnetic radiation from wireless charging does no harm. Others talk about the great danger to which the human body is exposed.

So how much electromagnetic energy is emitted by the Qi system? Very little. The Qi principle has been used in electric toothbrushes for many years without affecting people's health. The scheme of the charger is such that due to the small area of ​​​​its action, electromagnetic radiation is extremely limited. It exists only in the immediate vicinity of the wireless transmitting station and only when the gadget is on it. EMI is further reduced by additional shielding in the transmit and receive coils.

Wireless Power Consortium

The Wireless Power Consortium (WPC) was founded on December 17, 2008. At the same time, a unified program for the development of this technology was approved.

The Qi wireless charging standard ensures its versatility for all Qi-compatible electronic gadgets. This means that every device compatible with it can be charged at any Qi-compatible station. The WPS has 250 members including market leaders Samsung, Nokia, LG, Panasonic, HTC, Sony, Microsoft and Motorola, making it the largest association of manufacturers supporting wireless charger types.

As the number of Qi-enabled products increases, it's important to make sure every mobile charger works correctly with all Qi-supported gadgets, said WPC Chairman Menno Treffers. This is facilitated by a constantly updated database created by Testronic, which makes it easy to determine whether New Product compatible with previously certified products. The Qi wireless charging standard has become one of the most important technical developments for users of phones and tablets, which are now used daily in work and life.