• Micro USB connector pinout. Budget repair of USB cable - micro USB

    Hello friends! I think it happened to some people when you plugged something into the front USB input, left it and walked away. One fine day, after such forgetfulness, you return and see that the USB port is broken. Well, it’s broken and broken, nothing can be done. But what if the computer does not turn on? It's not so nice anymore, is it? You have to climb inside, turn off the front USB port, while pulling out the wires from the motherboard.

    And after some time you thought - I still need this front USB input, it’s convenient, I need to do something. And what? In this article we will look at how to resolder a USB port and make it functional. Of course, if your port is broken open, you will have to order a new USB port.

    We will need:

    • One or two USB ports
    • Some cable
    • Soldering iron, solder, wire cutters
    • Glue gun (depending on the situation)
    • Old cables connected to the motherboard or new ones for USB ports

    So let's get started. First, we disconnect the wires from the old, broken port, while the other ends of the wires can be left plugged into the motherboard, this will save yourself time. You also need to remove the USB port itself from the case and look at the condition of the case mount. Next, I took out a new port and tinned the contacts on it, then we need to cut off four pieces of wire, not very long, strip them and tin them.

    Afterwards, we need to decide what we solder where. On the Internet, I found a very good diagram found on the website rones.su.

    In the photo, we see: four colors - red, white, green, black. These colors will most likely match the colors of the cable that you already have plugged into your motherboard.
    Red – voltage + 5 Volts, white, - “minus” contact for data transfer, green + contacts for data and black, GND = minus, ground.

    Next, I simply soldered pieces of cable, yellow and brown, to the port. After this, we need to deal with the contacts from the motherboard, they may be intact and you won’t have to solder it all, and you can just plug them into the corresponding contacts.

    Afterwards, we need to clean and tin the contacts coming from the motherboard. After this, carefully solder the red wire from the USB cable with the wire going to the red contact of the USB port. We also solder the rest, white with white, green with green, black with black, or connect them together, whatever suits you.

    When everything is soldered, you need to figure out how to connect it all to the motherboard, if you had disconnected or pulled out the contacts from the motherboard. The best way is to find the instructions - the datasheet for your motherboard. In my instructions, I found the following pinout.

    Hi all. Today I will tell you in detail and show you how to change micro-USB connectors and other small things, on your knees,” i.e. at home, without special skills and special professional expensive paraphernalia and substances. Simply armed with inspiration, always helpful optimism, ingenuity, perseverance, patience and enough time.

    Yesterday they brought me a smartphone for repair Lumia Denim 630 with a faulty power socket, with the words: “Shows charging - but doesn’t want to charge!” The smartphone looked monolithic, without screws or latches, I thought: Well, that’s a waste! Now you’ll have to warm it up with a hairdryer!”, although after fiddling around it turned out that it’s easy to open, since the insides lie in a lid-“trough” that can be easily separated (on the internal latches). Those. Nokia developers have thought out everything in a military way.” For this I give them a tasty like!

    The socket appeared to be in good condition outwardly, no cracks were found in the soldering joints, which means, as often happens, the fault lay in worn out contacts inside the connector. I decided to boldly change it to a new one. After the repair, I dismantled the old socket and indeed the contacts were covered in dirt, oily felt, and looked worn out. I forgot to take a photo, but in general, see what kind of dead connectors there are, see the photo attached to the article.

    A sure sign that the socket needs to be replaced

    I bought the nests on Ali Express, in a bunch of about 100 pieces, 10 types, which is convenient.

    Set of micro-usb sockets

    I found something suitable, but not identical, which had to be modified and filed.

    The nest needs to be adjusted

    As it turned out later, despite the almost external similarity of the socket, the gold-plated contacts on it did not fit in height, that is, they hovered above the board! Take note!

    I adjusted the socket, but did not notice the discrepancy with the original

    I had to select a new nest, file it again, and adjust it, since I didn’t have what I needed.

    The nest needs to be adjusted

    When adjusting, a slight misalignment of the socket was revealed, i.e. opening the fastening locks of the socket, which had to be put in place, soldered and slightly adjusted to the smart cover with a sharp knife.

    The nest is adjusted

    And all because the nests ordered in bulk are cheap, which means they are simpler, made of not very durable metal, in comparison with the original nests. Native nests, as a rule, are very expensive, made well, reliably, but you can’t stock up on them for any occasion. Ordering relatives in China and waiting tediously is problematic. I decided by disassembling the old nest, weighing the pros and cons, and comparing price tags in Ali.

    For desoldering, I use a special hot air gun, although you can get by with a construction hair dryer, while being vigilant and attentive so as not to fry everything all around.

    Soldering gun

    Be sure to cover all plastic parts, capacitors, with confectionery foil or chocolate, otherwise they may melt! Then the damage to your smart phone may come suddenly and unexpectedly! 🙂 I.e. First, you warm up the entire board in a circular motion so that it doesn’t get driven by the propeller from the temperature difference, and then you heat the socket itself in a circular motion (about 300 degrees, check with a multimeter’s temperature sensor or using your intuition and your fingers). Before warming up, it is advisable to simply solder the socket with regular solder with flux or rosin (mix your tin with the factory one, this will make desoldering easier), since the factory solder on the board is often lead-free, which causes problems with soldering the socket.

    By the way, for ease of work, I get by with an ordinary silicone pastry mat, since professional roads are expensive.

    My soldering mat

    It holds high temperatures and nothing slips on it, i.e. the thing is practical and appropriate. I also use a special board holder with alligator clips, with which I conveniently fix the board.

    Board holder

    I purchased the mat and holder from Ali. In general, you can do without them, including the consideration. 🙂

    After desoldering, I use braid moistened with flux or rosin, leaning it with a soldering iron and moving them along the tracks and holes with tin, also pre-lubricated with flux.

    desoldering braid

    As a result, the braid absorbs all the interfering solder, leaving everything around clean (cool idea!). The only thing keep in mind is not to tear off the tracks and contact patches with the braid! This also happens! Be careful and take your time!

    I forgot to say that desoldering the socket with a soldering iron is problematic and risky. Of course, with good experience, you can also desolder in a sophisticated way - with the help of one large drop of solder, covering the entire socket with it and making sure that you don’t “bump” or stick adjacent parts to your mega-drop, etc. But still, this is done masterfully by people with a full hand and experience. Another option, in workshops earlier (when there were no hair dryers, during the USSR) they made (bought) special attachments-stings for the necessary connectors and sockets, which made it possible to supply heat to all the required areas at once and easily desolder them. This was an excursion, but for you it’s still easier to use a hot air gun.

    Special tips

    Ideally, workshops successfully use a special microscope for soldering small parts. I use magnifying glasses, since I can’t afford a good microscope yet, and taking a cheap one is just a waste of money.

    Illuminated magnifying glasses

    I also use a set of clock screwdrivers for disassembly and assembly; I also use them with pleasure as convenient small cleaners (from rosin on the board), pickers, pushers, lifting element legs, etc. I bought it at the nearest hardware store for a symbolic amount.

    Set of cheap watch screwdrivers

    The varieties of tweezers that I purchased from Ali and Fix-Price help a lot.” In important cases, women's cosmetic tweezers may come in handy. 🙂

    The tip of your family forty-watt soldering iron will need to be sharpened at an acute angle and with a slightly rounded end in order to carefully and effectively crawl up to the legs of the socket and painlessly for neighboring radio elements.

    Sharpening the soldering iron tip

    Or simply wrap copper wire around a tip and use it as a thin tip, in common parlance: “Mini soldering iron in a hurry”!

    Mini soldering iron

    It is advisable to buy a cheap power regulator for the lamps, which you will use to regulate the temperature of the tip, so that the rosin on the tip does not quickly turn into carbon deposits, so as not to overheat the conductive paths and so that they do not fly off.

    Lamp power regulator

    Of course, you can do it without a power regulator, but then you will have to solder with short touches so as not to overheat the tracks and tediously often clean the tip from black rosin oxides. And again - and this is the art of the possible, on the verge of risk. Decide for yourself.

    Let's continue. Before soldering, I washed off the used flux from the board with a toothbrush soaked in alcohol (you can also use vodka, but it’s not quite suitable because of the oils), brushing it towards the edges of the board so that the old flux does not smear on the board, fly off the board and led to corrosion of adjacent copper tracks. In general, this generally applies to almost all fluxes, no-clean and neutral, and also applies to rosin, since they are all aggressive to one degree or another and their evaporation is harmful to health to one degree or another (ventilate the room!). Therefore, it is advisable to wash off with alcohol, detergents, etc., and scrape off the rosin and rinse with alcohol (under the rosin, it can also corrode the tracks!). Next, I looked to see if the contact pads were clean and soldered (there shouldn’t be a lot of solder, i.e. no slides, just soldering so that the socket lays evenly and is soldered), lubricated the soldering areas with flux (see the photo for flux), laid it down, taking aim.” carefully on the seats so that the socket then coincides with the back cover and solder, periodically replenishing the tip with solder. Well, or if your solder is in the form of a thin wire, bring it to the place of soldering with a tip. If you only have rosin, then simply pick up solder with a tip, then dip it in rosin and quickly, before the rosin on the tip turns into a nasty black mass due to overheating, solder the necessary contact pins to the socket.

    Afterwards, be sure to check how you soldered, whether everything looks nice, whether anything is sticking out, or whether there is a so-called. ,snot” between the contact pads, as this can cause a short circuit and is fraught with more serious damage to the device. Use a little braid, if you can’t remove the snot with a sting, it will take away excess solder and remove tin under the socket leg. If a little remains, then lubricate the area with rosin and lightly use a sting to tear off the remaining tin between the contacts. But don't overdo it, the solder should be in the form of a sufficient droplet covering the contact for a strong contact. Do not skimp on flux (rosin) so that the soldering is electrically conductive (and not the so-called “cold” or “dry” soldering, which does not conduct current).

    Now, partially, without screws, we assemble the smartphone, connect the cables, turn it on, check for functionality, if everything is fine, charging is in progress, the battery shows that it is accumulating charge, then we finally assemble it by screwing and closing the back decorative cover.

    To clarify the process of replacing the socket, I cut you gifs from a video of a professional working. Look and listen.

    Micro USB connectors are built into many modern devices, but there are also connectors of another type - Mini USB, which require a separate special cable. Many people have a logical question: why not replace the Mini USB socket with Micro USB.
    Is it easy to re-solder a USB socket yourself without a soldering station, and what difficulties might a person without experience in electronics repair have when replacing a USB connector?
    Let's look at the process of replacing a Mini USB connector with a Micro USB in detail!
    First of all, you should know that these connectors most often do not have the same contact pads for soldering to the board, nor the pitch between the contact pins!
    If these difficulties do not scare you, and you still decide to replace the Mini USB connector with Micro USB, be sure to take care of insulating all contacts of the connector!

    As for tools, to replace the USB connector yourself you will need:
    1. High-quality low-melting solder and acid-free flux.
    2. A desalination pump, at least a simple one, is not required, but is desirable! It will help you desolder parts much faster!
    3. Braid for removing solder.
    4. Board cleaner or regular alcohol. Even if you use professional no-clean flux, it won’t hurt to wipe the board after soldering!
    5. Heat-resistant Kapton tape.
    6. It is very desirable to have a printed circuit board holder of at least the simplest type!
    7. Soldering station or soldering iron with thermal stabilization! Without them there is a high probability:
    - parts overheating! Overheated PCB traces usually just peel off!
    - its underheating! If the solder is not flexible enough and hardens quickly, you risk tearing off the part along with the contact pads of the printed circuit board! This is especially true when replacing Micro USB, Mini USB and other similar connectors!

    The process of replacing a USB connector consists of several stages:
    1. First of all, the device is completely de-energized, disconnected from the network and autonomous power supply (the batteries must be disconnected)!
    2. All low-melting parts near the connector are usually protected from melting by sealing with Kapton tape.
    3. Acid-free flux is applied to the area where the USB connector is removed.
    4. Refractory solder is removed and low-melting solder is applied.

    The more solder you can apply, the easier it will be to desolder the USB connector with a soldering iron.

    5. Moving the soldering iron evenly, try to simultaneously warm up all the contact pads of the connector and its leads.
    6. Carefully remove the connector from the board, first making sure that the solder is sufficiently heated. It is better to remove the connector with ceramic tweezers, rather than ordinary metal ones!

    7. All contact pads are cleared of solder so that their surface becomes smooth!
    8. If the Mini USB connector is replaced with Micro USB, and the contact pads do not match, Kapton tape is glued to the board. It is needed to prevent short circuits!

    9. It is very important to accurately align the Micro USB socket on the board! Please note that the protruding metal part of Micro USB plugs comes in different lengths!

    A Micro USB socket placed too “deeply” in the case will not provide reliable contact with the plug contacts due to the fact that its plastic will simply rest against the case! Conversely, a connector soldered too close can easily break due to sideways distortion when pulling out the cable!

    All connector pins must be carefully tinned and make sure that the solder actually penetrates the metal! If this is not done, the connector may simply fall off or move when inserting/pulling out the connector!

    Having precisely positioned the USB connector, solder its mounting pins.
    10. Then solder the power pins and (if necessary) signal pins.
    If the pitch between them does not match, wires (“hairs” of thin wire) are usually used for connection. However, please note that the power conductors ("+" and "-") must have a sufficient cross-section!
    11. The attachment of the Micro USB connector to the board can be strengthened by soldering an additional bracket made of tinned wire (necessarily hard).

    Of course, you need to solder it carefully so as not to melt the connector and not to cover its holes for fixing the Micro USB plug with solder!
    12. After replacing the USB connector, thoroughly rinse the board from flux and make sure there are no “snot” (solder particles) on it, which can cause a short circuit! Of course, it is better to “ring” all soldered contacts with a multimeter before assembling the device!

    The USB (Universal Serial Bus) interface has been in active use for 2 decades, and during this time several standards have been created. This first happened in 1997, when a corresponding connector appeared on motherboards. Today we will talk about USB standards and pinouts, but first you need to highlight the benefits tires.

    One of the main ones is Plug & Play support. Now, after connecting the device, you no longer need to manually install the necessary drivers and restart the personal computer.

    The bus not only allows the transfer of information, but also provides power to the connected device. As a result opportunity arose create mobile network and sound cards, as well as other types of controllers.

    USB versions

    Currently created 3 standards this interface. The main differences between them are not the pinout of the USB connector, but the speed of information exchange. At the same time, compatibility of new versions with previous ones is ensured, which makes life much easier for users.

    Type 1.1

    This standard is capable of providing transmission speed information up to 12 Mb/s. At the time of its creation, this was a good indicator, but there was still a faster interface - IEEE 1394 or FireWire (up to 400 Mb/s), developed by Apple. However, USB 1.1 became quite widespread and was used for several years.

    Among the main characteristics of this specification it should be noted:

    • Possibility of connecting more than 100 devices, including hubs.
    • Maximum cord length 3 m.
    • The bus voltage is 5 V and the load current is 0.5 A.

    Type 2.0

    With the advent of complex devices, such as digital cameras, the need for a faster interface arose. The result was the USB 2.0 version, which provided information transfer speeds of up to 480 Mb/s. Availability hardware compatibility with the 1.1 standard allows you to use older devices, but the bus throughput in this situation is sharply reduced.

    It should be taken into account that the actual throughput of USB 2.0 differed significantly from that specified in the specification. This is due to the implementation of a protocol that allows delays in the transmission of data packets. In recent years, a lot of devices have appeared, the normal operation of which required a large throughput tire.

    Type 3.0

    This is a new standard, the mass distribution of which began in 2010. It allows you to transfer information at speeds of up to 5 Gb/s. Although the pinout of the USB connector 3.0 has some differences from the 2nd version, they are fully compatible. To distinguish the connectors of these standards, USB 3.0 sockets and plugs are marked in blue.

    There are also certain inconsistencies in the wiring of connectors. The rated current has been increased to 0.9 A. As a result, the number of peripheral devices has increased, the operation of which no longer requires a separate power source. They have their own classification and USB connectors:

    • Type A is designed to connect to a socket installed on the computer motherboard or hub.
    • Type B is used in peripheral devices (printers).

    Connectors of the second type are quite large and cannot be installed on portable gadgets. To correct the situation, micro- and mini USB standards were created.

    Pinout of USB 2.0 connectors (types A and B)

    Since the connectors of the first versions of the universal serial bus are not physically different, it is enough to know the wiring of the latest standard. The first contact is supplied with 5 V power, and the 2nd and 3rd wires are used to transmit the signal. The USB cable pinout by color is as follows:

    • 1 - red.
    • 2 - white.
    • 3 - green.
    • 4 - black.

    USB 3.0 connector pinout

    In the latest version of the standard, instead of 4 contacts, 9 are used. The color scheme of the wiring is shown in the figure and looks like this:

    • The assignment of pins 1 to 4 is similar to the previous version.
    • Wires 5−6 and 8−9 are used respectively for transmitting/receiving data via the Super Speed ​​protocol.
    • 7 - mass of signal wires.

    Type B connectors version 3.0 are not compatible with previous standards.

    The pinout of mini-USB is similar to micro, but in the third version of the interface only the latter type of connector is used. Micro-USB 2.0 has 5 contacts, however, only 4 are used. In the latest version, the number of wires has been doubled. Contacts 1-5 perform the same functions as in the connectors of the previous standard, and the rest are designed to solve the following tasks:

    • 6−7 and 9−10 - respectively for transmitting/receiving data via a high-speed protocol.
    • 8 - ground of information wires.
    ​

    Micro USB pinout for charging

    Although all mobile gadgets charge via USB, there is no single standard, and each manufacturer has developed its own scheme. You can use any power adapter to recharge the battery. For example, in an iPhone, for this you need to connect pins 2, 3 to 4 using a resistor with a nominal resistance of 50 kOhm, and from 5 to 75 kOhm. The main competitor Samsung Galaxy has a simpler pinout of the micro-USB charging connector. You will need to place a jumper between pins 2 and 3, and connect 4 to 5 with a 200 kOhm resistor.

    It has been developed since 1994, and the development team consisted of engineers from leading companies in the field of IT technologies - Microsoft, Apple, Intel and others. During the research process, one goal was pursued - to find a universal port that could be used for most devices.

    Thus, users were provided with a USB connector, which was almost immediately supported by various developers and began to be actively used in a variety of devices, from personal computers to mobile gadgets. However, it so happened that cables with such connectors could not be used everywhere, and they themselves were different, and therefore some require unsoldering a mini-USB connector in order to make the appropriate adapter.

    However, few people know how this procedure should be carried out correctly.

    Concepts you need to know

    Wiring a USB connector begins with learning the basic concepts:

    • VCC - positive potential contact For modern USB cables, the indicator of this contact is +5 Volts, it is worth noting that in radioelectric circuits this abbreviation fully corresponds to the supply voltage of PNP, as well as NPN transistors.
    • GND - negative potential contact of the power supply. In modern equipment, including various models of motherboards, this device is connected by a housing in order to provide effective protection from static electricity or any external sources of electromagnetic interference.
    • D- - information contact having zero potential, regarding which information is broadcast.
    • D+ is an information contact that has a logical unit. This contact is used to broadcast information from the host to the device or vice versa. At the physical level, this process represents the transmission of rectangular pulses with a positive charge, while the pulses have different amplitudes and duty cycles.
    • Male is the plug of this connector, which is often called “male” among modern users who wire the USB connector for a mouse and other devices.
    • Female - the socket into which the plug is inserted. Users are called "mother".
    • RX - receiving information.
    • TX - information transfer.

    USB-OTG

    OTG is a method of connecting two peripheral devices via a USB cable without the need for a computer. Also, such a pinout of a micro-USB connector is often called USB-host in professional circles. In other words, a flash drive or some kind of hard drive can thus be directly connected to a tablet or mobile phone in the same way as to a full-fledged personal computer.

    In addition, you can connect mice or keyboards to gadgets, if they support the ability to use them. Cameras and other gadgets are often connected to printers in this way.

    What restrictions does it have?

    The limitations that this type of micro-USB connector has are the following:


    For example, if we are talking about connecting some kind of USB flash drive to the phone, then in this case the “USB_AF-USB_AM_micro” adapter is most often used. In this case, a flash drive is inserted into the connector, while the plug is connected to the mobile phone.

    Cable Feature

    The main feature that distinguishes the wiring of a USB connector in the OTG format is that in the plug, pin 4 must be connected to pin 5. In a standard data cable, nothing is soldered to this pin at all, but this plug is called USB-BM micro. It is for this reason that you need to get to the fourth contact, and then use a jumper to connect it to the GND wire. After this procedure, the plug will be renamed USB-AM micro. It is the presence of a jumper between these contacts in the plug that allows the device to determine that some kind of peripheral device is about to be connected to it. If the device does not see this jumper, it will act as a passive device, and any flash drives connected to it will simply be completely ignored.

    How are devices identified?

    Many people believe that when connecting in OTG mode, both devices fully automatically determine which of them will be the host and which will be the slave. In fact, in this case, only the user determines who exactly in this case will be the master, since in which device the plug equipped with a jumper between 4 and 5 contacts will be inserted, then of them will be the host.

    How to make it?

    Through the translucent insulation you can see several multi-colored wires. You will need to melt the insulation near the black wire, then solder one end of the jumper to the GND pin. On the opposite side you can see a white wire, as well as an unused pin. In this case, we need to melt the insulation near the unused contact, and then solder the second end of the jumper to it.

    It is worth noting that the wiring diagram for a micro USB connector is much simpler.

    The unraveled plug, which you equipped with a jumper, will need to be insulated, for which a specialized heat-shrinkable tube is used. After this, you will just need to take the “mother” from the extension cord and solder it to our color-matched plug. If the cables are shielded, then you will also need to connect the shields, among other things.

    Can it be charged?

    If peripherals are connected to the device via OTG, then it will have to power it, which can significantly reduce the overall operating time of the device from the built-in battery. In this regard, many people wonder whether it is possible to recharge such a device through an external source. This is possible, but this requires support for a special mode in the device, as well as a separate wiring of the USB connector for charging.

    In fact, the charging mode is most often provided by modern gadget developers, but not everyone allows such a procedure. It should be noted that to switch to this charging mode, a separate USB connector wiring diagram must be used, in which the contacts are closed through a separate resistor.

    Read more: