Schematic diagram of the iPhone charger. How it works Lightning cable

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Viktor Pankov sent interesting link to an article that describes in detail the features of the pinout of USB connectors for correct charging various gadgets, after all, it's no secret that gadgets often refuse to charge from simple USB port of the drive or computer, or do not behave as you would like.

Majority modern gadgets (mobile phones, smartphones, music players, e-books, tablets, etc.) supports charging via the USB mini/micro socket. There may be several connection options:

The device can be charged from a PC via a standard data cable. Usually this is the USB_AM-USB_BM_mini/micro cable. If the device requires more than 0.5A of current to charge (which is the maximum that USB 2.0 is capable of), then the charge time can be painfully long, up to infinity. The USB 3.0 port (such a blue one) already gives out 0.9 A, but even this may not seem enough to someone.

Through the same data cable, your device can be charged from a native charger(network or car) equipped with a 4-pin USB-AF socket, like on a computer. Of course, this is no longer a real USB port. The charger socket only outputs approximately 5V between pins 1 and 4 of the 4-pin socket (positive on pin #1, minus on pin #4). Well, in between different contacts sockets can be installed all sorts of jumpers and resistors. What for? This witchcraft will be discussed below.

The gadget can be connected to a third-party or homemade charger that provides 5 volts. And this is where the fun begins...

When you try to charge from someone else's charger with a USB output, your gadget may refuse to charge under the pretext that the charger allegedly does not suit it. The answer is that many phones / smartphones “look” how the Data + and Data- wires are disconnected, and if the gadget doesn’t like something, this memory will be rejected.

Nokia, Philips, LG, Samsung, HTC and many other phones will only recognize the charger if the Data+ and Data- pins (2nd and 3rd) are shorted. You can short-circuit them in the USB_AF socket of the charger and safely charge your phone through a standard data cable.

If the charger already has an output cord (instead of an output jack) and you need to solder a mini/micro USB plug to it, don't forget to connect pins 2 and 3 in the mini/micro USB itself. At the same time, you solder plus on 1 contact, and minus - on the 5th (last).

At iPhones in general, some occult requirements for switching the charger socket: the Data + (2) and Data- (3) contacts must be connected to the GND contact (4) through 49.9 kΩ resistors, and to the + 5V contact through 75 kΩ resistors.

Motorola"requires" a 200 kΩ resistor between the 4 and 5 pins of the USB micro-BM plug. Without a resistor, the device does not charge until complete victory.

For charge samsung galaxy in USB plug micro-BM, a 200 kΩ resistor must be installed between pins 4 and 5 and a jumper between pins 2 and 3.

For a more complete and "humane" tablet charge Samsung Galaxy Tab recommend another circuit: two resistors: 33 kΩ between +5 and jumper D-D+; 10 kΩ between GND and jumper D-D+.

Apparatus e-ten("Raccoon") is not interested in the state of these contacts, and will support even a simple charger. But it has an interesting requirement for charging cable- "Raccoon" is charged only if pins 4 and 5 are shorted in the mini-USB plug.

If you do not want to mess with a soldering iron, you can buy USB-OTG cable- in his mini-USB plug, contacts 4 and 5 are already closed. But then you still need a USB AM-AM adapter, that is, “dad” - “dad”.

The Ginzzu GR-4415U car charger, which claims to be universal, and its analogues are equipped with two output sockets: HTC / Samsung and Apple or iPhone. The pinout of these sockets is shown below.

For power or charge Garmin navigator a special data cable is required. Just to power the navigator through the data cable, you need to short-circuit pins 4 and 5 in the mini-USB plug. For recharging, you need to connect 4 and 5 pins through an 18 kOhm resistor:

So, if you want to convert a regular memory into a USB charger for your phone:

Make sure the device is putting out about 5 volts DC.

Find out if this charger can provide a current of at least 500 mA

Make the necessary changes to the wiring of the USB-AF socket or USB-mini/micro plug

Troubleshooting Popular iPhone smartphones can be a daunting task due to their built-in batteries. But they can often be the cause of the problem. To identify and fix this issue, a small device was created that can charge the iPhone battery, and there is also the ability to check the battery status, which can be considered a microcontroller or in another way. The device consists of 6 battery connector boards (for iPhone 4, 4C, 5, 5C/s, 6, 6+) and the main charging board.

iPhone Battery Tester Diagram

Batteries sometimes show no voltage when tested with a conventional multimeter. It is possible that the LiPo cells are actually completely dead, although this usually means that the battery has gone into protection mode. This can be caused by various reasons, including damage to the controller or a short circuit. This system can reactivate a battery that has entered protection mode by simply connecting it to the main charging board.

Battery Connection Boards

iPhone batteries can be connected to the main board through a 6-pin keyed connector to prevent wrong connection. There is also the possibility of adding additional connection boards with batteries. different types in the future (6s, 6s+, Samsung, etc.).

Charging board

The memory board contains a charging circuit, a microUSB power port and connectors. On the MCP73831 chip, lithium charging is performed. . It is designed for 3.7V battery voltage, but can also be used for charging under higher values. Cutoff voltage 4.2 volts. Two LEDs provide an indication of charging status. There is a 2A fuse to prevent overcurrent - this is the protection of the microUSB port. The programming resistor (R2) determines the maximum charge current. A value of 2K sets the MCP73831 to a maximum of 500 mA charge current.

Connector pinout

VBAT: connected directly to the battery positive terminal (and charge output MCP73831)
GND: ground
5V: microUSB socket input
GAS: protection contact
NTC: battery thermistor
STAT: Can be used to read the charging status by the microcontroller
PROG: Can be used to set charging current or disable charging

Apple, as you know, does not sell spare parts, so the only option is to pick up the ones you need yourself. All the details in the diagram are common and should be available in most major online marketplaces.

The inner world of a difficult accessory.

The real scourge for owners of iOS devices is Lightning cables. There are many, they are different, but you can not choose all.

Let's figure out the device of this seemingly simple accessory with a whole arsenal of secrets.

In bondage Lightning

Apple has never been shy unilaterally come up with standards and transplant their users to them.

While manufacturers mobile devices the last decade confidently sat on the type of charging sockets DC with a variety of plug diameters, for their players iPod Apple chose the interface firewire.

Apple met the smooth transition of thousands of brands that produce smartphones on miniUSB with a unique 30-pin port in the first iPhone.

Now the "single standard" in the world mobile gadgets connector remains microUSB with the prospect of being replaced by USB Type-C . Meanwhile, on iOS devices, he registered Lightning, and for a long time.

Find a charging cable " conventional smartphone" very easy. But Lightning - not so much. Therefore, among the owners of Apple technology, it is customary to take it with them.

The niche of "spare", consumable, travel cables for iPhone and iPad was promptly closed Chinese. Here is just one “but”: it is not so easy to fake them.

What's inside Lightning and why the original is expensive

To understand why Apple remains a company whose accessories sometimes seem unreasonably expensive can only be understood after a technical opening procedure.

Note: we breathe evenly Samsung. Just a comparison of the South Korean and American manufacturer.

Before us are two original accessories for smartphones from companies that have been the main competitors in the mobile device market for several years. The cost of the cable from Samsung is in the area 500 rubles. The original Lightning cable for iOS devices will cost 1590 rubles, 3 times more expensive.

Let's get a scalpel and try to figure out what is the reason for such a difference in price. I must say right away that Samsung plastic is cut very easily. And it’s not so easy to take a clip in Lightning with “bare hands” - powerful protection against penetration is provided.

We get to the insides and observe.

The best board option that you can find in microUSB looks like this:

In the worst case (and it will be a really original cable, but from another manufacturer), you will not even see a voltage rectifier. Just four multi-colored wires with braided shielding (which is also often saved on).

After the torment of disassembling the original Lightning lace, we are greeted by this “inner world”:

And a larger shot of the miniature board:

Hidden inside Lightning full microcomputer, which not only analyzes the entire process of recharging an iOS device, but also facilitates the operation of the accessory by the user.

And if until today you were puzzled by the cost of the original Lightning cable - now you know that it's all about the components and quality.

What happens inside Lightning and how it works

Under the protective metal cover of the Lightning plug is the circuit shown above. Of course, now we are talking about the original, and we will touch on the problem of Chinese consumer goods a little lower.

The board has four chips and several auxiliary computing devices responsible for transferring data to a computer and using a data connection cable. After iPhone connections to the charger, curious processes come to life inside this circuit.

The inner world of one of the chips

Two of the presented chips are very simple in design and consist of only a few transistors, the task of which is to convert the incoming signal electric current to a state that is maximally adapted to the battery installed in the smartphone.

Another chip with markings NXP NX20P3 provides control over the level of the current state of the battery, calculating the accumulated useful amount of charge.

The microprocessor installed in the cable helps to determine which side you insert the cable into the device connector.

The standard wiring for a Lightning cable looks like this:

And that's where Apple's magic comes into play. You do not need to think about which end to install the plug. Both the above microprocessor and the asymmetric placement of contacts are responsible for this.

Those. while you insert the cord, the filling automatically determines which pins to apply voltage to.

All these technologies are accompanied by dozens of patents that belong to Apple. But there is no limit to Chinese ingenuity: cables are faked with different accuracy and quality levels, they do not care about compliance with the law.

Therefore, Apple has provided for the protection of its accessories and has developed its own certification standard. MFI(Made for iPhone/iPad/iPod), and they decided to limit the connection of low-grade Lightning cables with one more, fourth chip, installed on the same miniature board of the original cord.

American Firewall against Chinese Lightning fakes

Hated by third-party accessory manufacturers, a chip with a number BQ2025. Without exaggeration, it can be called a "pass" to the bowels of the Lightning socket in the iPhone.

If there is no such chip on a non-original cable, the iOS device displays the following window:

At this point, you can actually throw away the “short string”: it will not adequately (or at all) charge the device, it will not allow you to synchronize data.

Important: Why does the message "This accessory or cable is not certified" appear?

The BQ2025 chip has a special dedicated digital block permanent memory , for the manufacture of which semiconductors are used. His name - EEPROM. A feature of EEPROM is the ability to rewrite information multiple times (up to a million times).

The memory size of the EPROM block is about 64 - 128 bits, but this is quite enough to store the unique key of every accessory for the iOS ecosystem in the world.

This block contains a key that allows you to identify "originality" - compliance with Apple standards and confirmation of the presence of official MFI certification. When connected, the key on the accessory is mapped to the value base on the iOS device. If one is not found, an error message pops up and it is impossible to work.

Manufacturers of counterfeit cables were partially able to bypass the protection. As an alternative to EEPROM, artisan firms use emulator, which is based on microcontroller 8051. He bypasses Apple protection, but is not durable, which is why the cable abruptly stops working with iOS.

One of 10 variants of Chinese creativity

Any other company would become hostage to its own technology. Think for yourself. On the one hand, Apple can at any time start producing smartphones that will only accept original cables. On the other hand, there will be real chaos in the accessory market, and the original Lightning already purchased by users will become incompatible with the new generation of devices.

So it's good that Apple does everything in portions. The EEPROM area of the memory is easily overwritten during the next iOS updates through iTunes apps. And very often, after flashing, Chinese Lightning refuses to work.

Add to this the DRM protection of multimedia files that the company so supports, and you can forget about the compatibility of non-certified accessories for displaying images and relaying music through the Lightning port.

Another problem that prevents anyone from starting the production of accessories is the inaccessibility and high cost of circuits. Remember the chip described above NXP NX20P3? The price of his scheme on the black market is $2,500!

And to start production, one scheme will obviously not be enough.

What is dangerous fake Lightning

Apple conceived the key system for a reason. In addition to income, they also thought about their reputation.

Have you often heard about exploding smartphones, bursting screens, leaking batteries and electric shocks when connecting the charger in the Android device environment? There are many such cases, they are not even paid attention to. There are only a few such situations in Apple technology, and each one causes a flurry of attention:

The main question is what accessory the victims used. In both cases - unoriginal. Do you understand now why this is so important?

Where and who, I think, is clear without words

You need to look at the root of the problem. Before buying a low-quality shoelace from a Chinese site, think about the consequences. Usage non-original Lightning cable may cause :

It quickly falls into disrepair. The braid cracks, the backlash of the plug appears.
Complete loss of compatibility after the update, described above. The result is money down the drain.
Well, if the iPhone just won't turn on. In the worst case, it can catch fire or explode from overheating. And, God forbid, during a conversation when connected to the network.
The life of the original cable is many times longer than the fake. Saving? It just seems that over time, the cost of supporting the "ecosystem" of Chinese cables exceeds that of the original ones.

In short, the original is worth it. And even if for some reason you don’t want to take a cable specifically from Apple, you can always find a certified, high-quality alternative. Sometimes even with an interesting "trick".

Most modern mobile phones, smartphones, tablets and other wearable gadgets support charging through the socket. USB mini-USB or micro USB. True, it is still far from a single standard, and each company is trying to make the pinout in its own way. Probably to buy a charger from her. Well, at least the USB plug and socket itself were made standard, as well as the supply voltage of 5 volts. So with any charger-adapter, you can theoretically charge any smartphone. How? and read on.

Pinout USB connectors for Nokia, Philips, LG, Samsung, HTC

Nokia, Philips, LG, Samsung, HTC and many other brands of phones will only recognize the charger if the Data+ and Data- pins (2nd and 3rd) are shorted. You can short-circuit them in the USB_AF socket of the charger and safely charge your phone through a standard data cable.

Pinout of USB connectors on the plug

If the charger already has an output cord (instead of an output jack) and you need to solder a mini-USB or micro-USB plug to it, then you do not need to connect pins 2 and 3 in the mini/micro USB itself. At the same time, you solder plus on 1 contact, and minus - on the 5th (last).

Iphone USB pinout

For iPhones, the Data + (2) and Data- (3) pins must be connected to the GND pin (4) through 50 kOhm resistors, and to the + 5V pin through 75 kOhm resistors.

Samsung Galaxy Charging Connector Pinout

To charge the Samsung Galaxy, a 200 kΩ resistor between pins 4 and 5 and a jumper between pins 2 and 3 must be installed in the USB micro-BM plug.

Pinout of USB connectors for Garmin navigator

A special data cable is required to power or charge your Garmin navigator. Just to power the navigator through the cable, you need to short-circuit pins 4 and 5 in the mini-USB plug. For recharging, you need to connect pins 4 and 5 through an 18 kΩ resistor.

Pinout schemes for charging tablets

Almost anyone tablet computer charging requires a large current - 2 times more than a smartphone, and charging through the mini / micro-USB socket in many tablets is simply not provided by the manufacturer. After all, even USB 3.0 will not give more than 0.9 amperes. Therefore, a separate nest is placed (often of a round type). But it can also be adapted to a powerful USB power source if you solder such an adapter.

Samsung Galaxy Tab Charging Socket Pinout

For the right charge samsung tablet The Galaxy Tab recommends a different circuit: two resistors: 33 kΩ between +5 and the D-D+ jumper; 10 kΩ between GND and jumper D-D+.

Charging port pinout

Here are some diagrams of the voltages on the USB pins, indicating the value of the resistors that allow these voltages to be obtained. Where a resistance of 200 ohms is indicated, a jumper must be installed, the resistance of which should not exceed this value.

Charger Port Classification

SDP(Standard Downstream Ports) - data exchange and charging, allows current up to 0.5 A.
CDP(Charging Downstream Ports) - data exchange and charging, allows current up to 1.5 A; hardware recognition of the port type (enumeration) is performed before the gadget connects the data lines (D- and D +) to its USB transceiver.
DCP(Dedicated Charging Ports) - charging only, allows current up to 1.5 A.
ACA(Accessory Charger Adapter) - PD-OTG operation in Host mode is declared (with connection to PD peripherals - USB-Hub, mouse, keyboard, HDD and with the ability to additional food), for some devices - with the ability to charge PD during an OTG session.

How to remake the plug with your own hands

You now have a pinout diagram for all popular smartphones and tablets, so if you have the skill of working with a soldering iron, there will be no problems with converting any standard USB connector to the type you need for your device. Any standard charge that relies on using USB, involves the use of only two wires - this is + 5V and a common (negative) contact.

Just take any charging-adapter 220V / 5V, cut off the USB connector from it. The cut end is completely freed from the screen, while the remaining four wires are stripped and tinned. Now we take a cable with a connector USB desired type, after which we also cut off the excess from it and carry out the same procedure. Now it remains just to solder the wires together according to the diagram, after which the connection is isolated each separately. The resulting case is wrapped on top with electrical tape or tape. You can pour hot glue - also a normal option.

Bonus: all other connectors (jacks) for mobile phones and their pinouts are available in a single big table — .

In iPhone 3GS charge management battery chip 338S0533-AE is in charge. Photo taken from ifixit.com.

Fragment main iPhone boards 4S. The power controller is circled in orange - a microcircuit marked 338S0973. Photo taken from ifixit.com.

To all the above features, you can add the strange behavior of your device when using non-original charger. For example, your iPhone or iPad may take a long time to charge, or, for example, continue to be discharged while performing some "heavy" tasks or programs while connected to the network.

And now, actually, the technical part. First in China, and then in Europe, they adopted the USB-based portable charger standard. At the same time, it should not be forgotten that according to the specifications USB port 2.0, it can supply current up to 0.5 A. At the same time, many smartphones and tablets consume more. For example, an iPad can be charged with a current of 2.1 A, how does this happen? In standard USB connector 2.0 type A there are 4 contacts, namely the "zero" contact, the power contact and two information - D + and D-. It is D+ and D- that are used in modern devices to identify the charger, after which the gadget's power controller will switch to "fast" or "slow" charging mode. In general, there is a standard that describes the interaction of devices with USB bus for charging purposes, including a standard for communicating with a computer's USB port, through which devices "negotiate" the maximum current. But back to inexpensive AC or car (DC) chargers. In the case of the simplest and most inexpensive (or simply old), only the supply contacts are separated inside the power supply. In this case, the charging device cannot determine the type of charger, and, for safety reasons, goes into slow charging mode. You may have observed that car charging bought on the market, the phone charges more slowly? Sometimes with a lot of consumption (for example, when navigating using online maps), it happens that the battery of an Android smartphone is discharged even when it is plugged into the charger :) The reason is that Android is ready to burn out the battery in 5 minutes. The reason is not that charging "can't give more current”, but that the gadget itself “does not take anymore”. And in order for the phone to "take more", he must be sure that he can do this. To do this, in branded chargers, the central contacts D- and D + are shorted to each other. In fact, short circuit contacts D- and D + is a signal to the phone that it can be charged with a current of up to 850 mA. Almost everyone does this major manufacturers, and, as a result, you can be sure that charging from HTC will charge samsung phone or LG. And if you have a charger or portable battery, from which the phone charges slowly, and you are absolutely sure that the device circuit can provide current up to 850 mA with a stable voltage and without interference under load, then you can carefully disassemble the case and close the central contacts.

Identification schemes for Apple and Sony chargers. Source DMAX14568EMAX/14568AE Datasheet.

But not everyone went this way. There were those who decided invent and patent the bicycle make your choice. These manufacturers include Apple and Sony, which have settled on their proprietary solutions. The scheme proposed by Apple is more complicated for the phone (in fact, the phone should have two comparators at the input that compare the voltage on D + and D- with some reference levels), but it provides different variants values, and as a result - good compatibility between devices and chargers. So the iPad (the mains charger of which is designed for charging current up to 2.1 A) can be charged from the charger for the iPhone, which is designed for a current of 1 A or even 0.5 A. There will be no overload of the power supply - the gadget correctly identifies the device to which it is connected, and switch to one of the slow charge modes. It should be understood that due to the use of a proprietary scheme, Apple devices may not properly charge from third-party USB power supplies (read: cheap Chinese trinkets that flood the underpasses and markets of the capital). Therefore, when buying chargers for iPhone, iPad or iPod, you need to pay attention to the packaging. Namely, the corresponding