Charger for Android smartphone: everything you need to know. Wireless chargers

Even after wireless Internet connections have become commonplace, transmitting energy without wires is still considered science fiction by many. However, over the past few years, active research has been carried out in this direction, and now the first commercial devices that allow equipment to operate without another type of wire are already available for sale.

The wireless charger market sector experienced a real boom in the fall of 2009, when companies, one after another, began to announce inductive charging devices. The first samples of wireless chargers were not certified, so they supported only a clearly limited set of chargeable devices.

The situation changed radically at the end of the summer of 2010, when the Wireless Power Consortium, which included the largest electronics manufacturing companies, approved a new standard for wireless power transmission Qi 1.0 with a level of no more than 5 W

The Wireless Power Consortium is currently working on the next version of Qi. It is known that the new version will allow you to transfer more energy over a distance and charge more “serious” equipment, such as netbooks, laptops, and tablets.

This icon (logo) marks all electronic devices that support Qi wireless charging.

Composition and operating principle of inductive charging

Source of energy. The basic operating principle of inductive charging is based on the use of the effect of electromagnetic induction. This requires two coils and alternating current, which will create a non-static electromagnetic field. The first coil is located in the transmitter and connected to the network.

Energy receiver. The receiver also contains a coil in which current occurs only when the electromagnetic field changes. This can be achieved by moving the receiver in space or by using alternating current on the transmitter. If anyone is afraid that he might be hit by a spark running between the transmitter and the receiver, then he is mistaken, since there is no transfer of charge through the air - the alternating magnetic field created by the first coil simply forces the electrons in the receiving device to move.

The basic operating principle of inductive charging is very simple and is based on electromagnetic induction. Unlike classic chargers, their wireless counterparts use an additional conversion unit, similar to a conventional transformer, instead of a copper conductor, which leads to a slight decrease in efficiency.

The efficiency of this unit, according to different manufacturers, ranges from 50% to 90%. The Wireless Power Consortium puts an intermediate figure at 70%.

The benefits of new wireless charger technology

Let's try to list all the advantages of the new technology:

Convenience. The phone owner simply places the device on a small flat panel, without worrying about connecting wires or accurately positioning the device on the transmitter.

Versatility. Users of certified equipment will be able to recharge it using any Qi-compatible charging model.

Economy. Although the overall efficiency of inductive charging is lower than that of traditional ones, due to the almost complete absence of energy consumption when idle (0.0001 W), they take the lead over long-term operation.

Practicality. The inductive charger is designed to be able to simultaneously “connect” several devices. Unlike traditional chargers, this does not require additional sockets.

Well, from an aesthetic point of view, the absence of unnecessary wires has always been a big plus.

Available wireless chargers

Transmission of energy over a distance is a truly new technology that has been developed for a number of innovative projects. In recent years, many large companies have been researching wireless power transmission for use in conventional technology. Suffice it to name Intel, Sony, Sanyo, Fujitsu, Energizer. And although some innovative developments never made it out of the laboratory, some products are already available on the market.

Powermat was one of the first to introduce inductive charging. Its models support iPhone, iPod, BlackBerry, and more recently Android.

Qi wireless charger - Powermat3

Such a limited list is due to the fact that initially not a single phone has a receiver for receiving energy. It is installed into the smartphone later along with a new battery and, of course, special battery versions are available only for the most popular models. Usually the battery with the receiver is slightly larger than its predecessor, but in general, due to the well-thought-out design, it practically does not stand out in the device.

GEAR4 takes a slightly different approach. Instead of a battery, the charger comes with a special case for the iPhone, which must be on the phone at the time of charging. The rubber pad does not need to be removed once the battery is fully charged as it can perform normal protective functions.

The most common wireless charger today Energizer Qi One of the first to be certified in accordance with the Qi 1.0 standard and can charge up to three devices simultaneously. At the same time, an additional USB port is located on the transmitter body, which allows you to add another device

Wireless charger - Energizer Qi

Wireless power transmission systems aren't just for smartphones. A year and a half ago, Energizer began releasing the Wiimote Induction Charging System for wireless controllers for the Nintendo Wii. Unlike analogs from other manufacturers, in this case you don’t even need to remove the silicone covers from the Wiimote. The cost of the listed chargers complete with battery usually ranges from $50 to $150

Another Energizer device, but this time highly specialized. Designed exclusively for charging Nintendo Wiimote

Although the Qi 1.0 standard does not provide the ability to transmit enough energy to power large devices, some manufacturers have developed their own systems for recharging laptops. More than a year ago Dell introduced a 16-inch model Latitude Z with a body thickness of just over 1.25 cm and a weight of about 2 kg, which can be charged wirelessly while on a special stand. The starting price of the laptop was $3645, and now, depending on the configuration, it is around $2000.

However, mass production of universal inductive chargers capable of charging laptops from any manufacturer will have to wait another couple of years.

The near future of wireless power transmission

It is obvious that in the near future all the efforts of researchers will concentrate on solving the following problems: increasing the efficiency of devices, increasing the amount of transmitted energy and distance. You can also expect that new inductive charging models will be almost universal and will be able to charge mice, portable consoles, phones, cameras, GPS and other devices.

Probably, soon all portable gadgets and mobile phones will be equipped with Qi-compatible receivers by default, so that they do not have to be purchased along with a new battery.

Last fall, Fujitsu announced that it would put its next generation of inductive chargers into mass production in 2012, which can charge mobile devices 150 times faster than early prototypes. Moreover, the efficiency of energy transfer in such models will be at least 85%.

In general, considering that a year ago Sony presented a working prototype of a system transmitting 60 W of energy, and WiTriCity announced the presence of devices capable of transmitting energy over a distance of 2 meters, it is possible that such technologies will become commonplace in a few years.

You can look into the future and a little further - already now Nissan demonstrates a prototype electric vehicle charger that can charge small electric cars in just 3 hours. At the same time, engineers claim that the efficiency of such a system is the same or even higher than that of conventional wired charging of cars.

There are no similar entries.

The warranty for online store products is one year for dishes and kitchen utensils, two years for garden equipment. Returns or exchanges are made using a warranty card and are regulated by the Law of the Russian Federation on the Protection of Consumer Rights. A mandatory condition for return or exchange is the absence of mechanical damage to the product.

We have been on the market for 18 years - we have shown and proven that we can and are able to cope with any tasks of supplying organizations, stores and individuals with high-quality and inexpensive tableware.

Conducting the transaction FROM AND TO - we accompany any order from the call, subsequent consultation and until delivery of the goods to the buyer’s warehouse.

More than 20,000 items of goods are constantly in stock - you don’t need to worry about empty shelves in your store.

We work very responsibly with possible defects - the client is important to us, first of all, not for a one-time sale, but for many years of cooperation.

Our warehouse packs goods very well; fragile goods are sent intercity in a crate.

Flexible payment terms allow our clients not to worry about empty shelves in their stores, and catering establishments not to worry about problems with serving. We will always accommodate the client and give him the most favorable terms for payment for the goods.

We work 7 days a week, 365 days a year - our wholesale and retail consultants are ready to promptly answer any question both through the website and via email. Our website is available around the clock - it is very convenient to place an order at any time of the day.

Our showroom and warehouse are located in one place - it is very convenient to come, touch the goods and immediately ship.

We are happy to provide pleasant bonuses and surprises to our clients. Constant win-win lotteries, sales, and warehouse cleanouts allow our customers to earn good money.

The European Parliament has supported a law that will oblige manufacturers of smartphones sold in the European Union to use a single charger.

The bill on a single charger standard was introduced late last year. During the voting, the project was supported by 550 deputies, 12 parliamentarians opposed it and another 8 abstained. Now the document must be approved by the European Council, which includes the prime ministers of EU member states. If the decision is positive, the document will come into force in 2017.

The publication notes that European consumers now use about 500 million mobile phones, while experts talk about about 30 different types of chargers. Often the same manufacturer uses different “chargers” for different phone models.

The application of the new law should make life easier for users who are forced to incur additional costs in case of device replacement. In addition, supporters of the law believe that from the moment it comes into force, the mass of electronics discarded annually will be reduced by 51 thousand tons.

However, the new law also has critics. Thus, one of the deputies noted that the use of a single standard can slow down innovation and complicate the task of designers. Finally, it is possible that prices for mobile phones will increase due to rising costs for manufacturers during the transition to the new standard.

Analysts believe that Apple, which has abandoned the use of the common microUSB format in favor of a proprietary connector called Lightning, may suffer the most from the application of the new rules, The Next Web clarifies. There is no information yet on how the manufacturer plans to comply with the requirements of the law. You might be interested

Nokia is losing popularity and is taking a desperate step

In the Orenburg store, the seller accepted such a bill and gave change - 35 thousand rubles

A contactless charger is a dream for every smartphone owner. Modern phones need to be charged regularly. You constantly have to connect them using a wire to the adapter. However, now you can choose wireless charging and forget about all the difficulties. Wireless phone charging is no longer a dream, but a common device used by millions of users.

For many decades, people have dreamed of the possibility of transmitting energy over a distance. This can often be found in fantasy novels of the 20th century. And then it happened. Chargers have come into use that charge consumer batteries from a distance. True, the distances are still very small, only a few centimeters, but this is already a confident step forward. And not theoretical, but practical.
At the moment, wireless contactless chargers for smartphones (BZU) are the most widely used. Just put your smartphone on the charger and it will start charging. No wires are needed from wireless charging to your smartphone. Everything works on the law of mutual induction. The phone rang, you calmly pick it up without fear of getting tangled in the wires, without fear of damaging the connector contacts, and you are also not strictly tied to your workplace.
So, at the moment, wireless chargers are no longer a myth. These are adapters that anyone can purchase. You can place the charger on a table by your bed at home or in a car on the dashboard.
But it is worth noting that not all phones and smartphones produced by various manufacturers are capable of charging from wireless chargers. Phones that support wireless charging have only recently begun to appear. You can find out which phones support wireless charging from the mobile phone store manager. But if your phone does not support this function, then I will describe below how to upgrade your phone or smartphone for these types of charges.

Principle of operation

The principle of operation of a wireless charger is based on the laws discovered by scientists Tesla and Faraday. These are the so-called phenomena of induction and mutual induction. Remember school physics. If current flows through a conductor, a magnetic field appears around the conductor. If another conductor is introduced into a magnetic field, then an EMF (Electromotive Force) is induced in it.

All transformers operate on this principle. If alternating current is applied to the primary winding of a transformer, a current is generated on the secondary winding, the magnitude of which will depend on the number of turns in the secondary winding. Wireless charging works on the same principle. And I will try to explain how wireless phone charging works. The source of electromagnetic radiation is the induction coil, which is located in the charger (acts as the primary winding of the transformer). Looks like a stand, charging cup or something similar. Connects to the mains directly or via an adapter. The device being charged also has its own coil (similar to the secondary winding of a transformer). If both coils are located at a sufficiently close distance from each other, then an alternating current is induced in the second coil, then it is rectified into a direct current and charges the gadget’s battery through the charge controller.

Any contactless charging for a phone or other device works on this principle, be it in a home or car. Most often we come across devices of the QI standard.

Wireless charger standards

Qi
The most common wireless charging standard is Qi. This standard was developed by the Wireless Power Consortium, abbreviated WPC, and is supported by many manufacturers such as Samsung, Nokia, LG and others. The Qi standard is read as Qi, which in Chinese is equivalent to the word “life.”

The operating principle is based on the law of mutual induction, as described above. The operating frequency of the BZU is 100-205 kHz. Efficiency 75-80%.
P.M.A.
Another popular standard is called PMA. Its principle also includes the law of electromagnetic induction. This standard was developed by Powermat in 2012. It is not as popular as Qi, but it also has its advantages.

The company focused its main efforts on developing a better electromagnetic field transmitter. And the operating frequency of the charger is 277-357 kHz.
This standard is mainly used in the USA. But still, the PMA standard is quite inferior to Qi.
Rezence (A4WP)
The operating principle of the Rezence standard is based on the law of magnetic resonance. This allows you to increase the transmitted power to 50 W, which is enough to charge more powerful devices, and even several devices at the same time. You can also increase the distance from charging to the gadget being charged.

But so far this standard is more theoretical and does not receive widespread support.

Where are wireless chargers used?

Since the invention of wireless charging, it immediately began to be implemented by all kinds of manufacturers to charge the batteries of various devices.
Toothbrush manufacturers were among the first to introduce wireless charging. The fact is that toothbrushes come into direct contact with water. This is where the invention of the BZU came in handy. After all, these devices do not have bare contacts. The toothbrush and charger have a good seal.

The corporation also keeps up with progress. They have introduced wireless charging for their Apple Watch.

But the most popular are wireless chargers for smartphones. What a convenience. Just put your smartphone on the charger and the charging process begins. No wires. He released a large share of smartphones with such chargers. Nokia also released smartphones with such chargers. In 2017, it released the iPhone 8 iPhone X smartphone, which can also be charged from a charger.
Often such devices are installed in public places. In cafes and restaurants, people are used to working using smartphones, communicating or having fun. The Internet takes up quite a lot of battery power.

To attract visitors and ensure that guests stay as long as possible in these establishments, the owners offer free Wi-Fi, but also, of course, contactless chargers for smartphones, which are built right into the establishment’s tables.

Many manufacturers also produce wireless car chargers for phones. The principle of wireless charging is very simple. The wire from this charger is inserted into the cigarette lighter socket, the charger itself is installed in a convenient place, taking into account that the phone will not fall off it while driving.

Benefits of wireless charging

There are a lot of advantages to being able to charge your phone using a contactless method. First of all, the main problem is solved, namely the adapters. Now there will be one universal panel for all devices at once. The wires will not wear out and the sockets on the mobile phone will not break too quickly. This is also especially important for a charging iPhone, because its repair is expensive.
When choosing a specific adapter, you can’t help but think about the advantages of contactless:

• Convenience. Can be used anywhere.
• It is possible to charge several phones at once.
• Over time, there are more and more devices that support this function.
• A minimum of electricity is wasted, although the efficiency of this charging is about 80%.
• and some other companies plan to offer a similar adapter right with the phone.
• Durability. The charger can last for many years.

Manufacturers

Many companies have taken up the issue of creating and developing contactless chargers for phones. Each of them is focused on specific features and is ready to satisfy the specific wishes of users. First of all, you need to consider chargers from smartphone manufacturers that have wireless charging enabled.

How to improve your smartphone yourself

As I wrote above, not all smartphones can work with contactless chargers. There is no receiving part inside these smartphones. But this is not a sentence. Today, in addition to wireless chargers, there are also separate receiving devices on the market.

They look like a sheet of cardboard the size of a matchbox. Inside this plate there is a receiving coil. The receiving part is of two types. The first option is that the receiving part is placed under the battery compartment cover of the smartphone and is connected directly to the battery.

The second option is that the receiving part is connected to the input connector and covered with a smartphone case.

Yes, there is another option. Smartphone cases with a built-in receiving part are available.

How to choose

Experts advise that before deciding which contactless phone charger to choose, decide whether the gadget supports this technology. Apple is specifically categorically against this practice, because they are focused on using original contactless adapters. However, many other manufacturers do not need such careful selection. Many gadgets accept modern phone chargers from different manufacturers.

Be sure to watch the video review of wireless chargers

Qi is the Chinese word for "energy flow" (pronounced "chee" in English) and a universal standard for battery-powered devices such as iPods, cell phones, and cameras.

Power transfer occurs due to the In this case, the receiver receives energy not through a traditional cable, but in a contactless way, thanks to the use of electromagnetic fields. The principle is very simple: the Qi transmitter, which is the base station, sends the necessary energy to the receiver.

Description of technology

The Qi wireless charging standard is based on magnetic induction between the flat coils of the transmitting and receiving device. The primary and secondary windings form two parts of the coreless charger circuit is shielded on the lower surface of the primary and upper surface of the secondary coil. This, as well as the close location, guarantees acceptable energy transfer efficiency. Additionally, it minimizes the user's exposure to the magnetic field.

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 installs 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 active human participation. In one implementation, several primary windings are created for this. Another option uses mechanical means to move the primary coil under the secondary.

Design elements

The power transmitter consists of two main functional blocks, namely a power conversion block and a communication and control block. The element of the first that generates the magnetic field is the primary coil. The second changes the transmitted power to the level requested by the receiver. In addition, a base station may contain more than one transmitter to serve multiple mobile devices, since one primary only communicates with one secondary at a time. Finally, the system unit provides power and controls the operation of several 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 for the subsystem connected to the receiver's power output. An example of such a subsystem is a battery.

Stages of communication

Once the transmitter communication and control unit is activated, 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 proposed voltage is high enough, then the ping phase begins.

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

Then the 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 to the base station, which contain information about the adjustment of the primary winding current, the received energy, the charging status, and the completion of the transfer.

What is a wireless charging point?

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

So, any Qi wireless charger will work with any Qi mobile receiver, regardless of brand and model. Many cell phones from different manufacturers, including Samsung, Nokia, LG, Sony, HTC and Motorola, already comply with the Qi standard and therefore can be connected to any charging station that meets its requirements. The number of compatible gadgets continues to grow as wireless power technology is supported by more and more companies. This allows you to charge battery-powered electronics with a single power source.

How it works?

The mobile charger is not a recent invention. Inductive power has been used in electric toothbrushes for many years. The process uses resonant inductive coupling between the base station transmitter and the mobile phone receiver. The primary coil continuously sends a test signal to the sender to check for changes in capacitance or resonance indicating the presence of a compatible phone. The transmitter modulates the charge and checks whether 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, contact between the receiver and transmitter is maintained. Once the battery is fully charged, they will go into standby mode. The universal charger is activated and transmits energy only if the connected gadget is on it.

The coils that transmit and receive energy are specially shielded to reduce electromagnetic radiation.

Main features of the technology

• A method of contactless power transfer from a base station to a mobile device, which is based on near-field magnetic induction occurring between coils.
• Transmits approximately 5 W of power using a suitable secondary coil (having a typical external dimension of approximately 40 mm).
• Operates at frequencies from 100 to 205 kHz.
• Supports two methods of placing on the base station surface:
  • guided positioning, where the user is assisted in correctly positioning the mobile device in a location that provides power through one or more fixed points;
  • random placement on the surface of the charging station.
• A simple one that allows your phone or tablet to guide the process.
• Considerable design flexibility for integrating the system into a mobile device.
• Low power consumption in standby mode (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 shorter. And every manufacturer and even every gadget has its own charger. And with each purchase their number increases. Ultimately, the user gets lost in a heap of various power adapters. Thanks to Q-technology, they become unnecessary, and tangled cables disappear, and these are not all the advantages of this technology.

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

Is electromagnetic radiation harmful?

Expert opinions were divided. On the one hand, many scientists confirm that a small amount of electromagnetic radiation from wireless charging does not cause harm. Others talk about the great danger to which the human body is exposed.

So how much electromagnetic energy is emitted by a Qi system? Very little. The Qi principle has been used in electric toothbrushes for many years without affecting people's health. The design of the charger is such that, due to its small operating area, electromagnetic radiation is extremely limited. It exists only in the immediate vicinity of a wireless transmitting station and only when the gadget is on it. Electromagnetic radiation 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 universality for all Qi-compatible electronic gadgets. This means that every compatible device can be charged at any Qi-compatible station. WPS has 250 members, including market leaders Samsung, Nokia, LG, Panasonic, HTC, Sony, Microsoft and Motorola, making it the largest group of manufacturers supporting wireless chargers.

According to WPC Chairman Menno Treffers, with the increasing number of products using Qi, it is important to ensure that each mobile charger works correctly with all Qi-supported gadgets. This is facilitated by the constantly updated database created by Testronic, which makes it easy to determine whether a new product will be 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 every day at work and at home.