Replacing the Mini USB connector (socket) with Micro USB without a soldering station. Micro USB repair using soldering
Universal USB buses are one of the most popular computer interfaces. They debuted back in 1997, and just three years later a new modification (2.0) appeared, accelerated 40 times compared to the original. However, despite such progress, manufacturers realized that the speed is still not enough to use external hard drives and other high-speed devices. And today a new USB interface (type 3.0) has appeared. The new standard exceeded the speed of the previous version (2.0) by 10 times. This article is devoted to the issue of wiring a USB connector. This information may be useful to radio amateurs who independently manufacture any USB adapters or devices that receive power via the USB bus. In addition, let's look at what the wiring of a USB connector like micro-USB and mini-USB is.
Description
Many radio amateurs have encountered a problem where an incorrectly connected USB bus port led to the burning of flash drives and peripheral devices. To avoid such situations, it is necessary that the USB connector is wired correctly, in accordance with accepted standards. The USB 2.0 type connector is a flat connector with four pins, it is marked AF (BF) - “female” and AM (VM) - “male”. Micro-USBs have the same markings, only with a micro prefix, and mini-type devices, respectively, have a mini prefix. The last two types differ from the 2.0 standard in that these connectors already use 5 contacts. And finally, the latest type is USB 3.0. Outwardly, it is similar to type 2.0, but this connector uses as many as 9 contacts.
Pinout of USB type connectors
The USB 2.0 connector is wired as follows:
The first wire (red), it is supplied with a DC supply voltage of +5 V;
The second contact (white), it is used for (D-);
The third wire (green), it is also designed to transmit information (D+);
The fourth contact (black color), zero supply voltage is supplied to it, it is also called the common wire.
As mentioned above, the micro and mini types are a five-pin USB connector. The wiring of such a connector is identical to type 2.0, except for the fourth and fifth pins. The fourth pin (lilac color) is the ID. In type B connectors it is not used, but in type A connectors it is connected to the common wire. The last, fifth pin (black) is the supply voltage zero.
type 3.0
The first four contacts are completely identical to the 2.0 standard; we will not dwell on them. The fifth pin (blue) is used to transmit information with a minus sign of USB3 (StdA_SSTX). The sixth output is the same, but with a plus sign (yellow). The seventh is additional grounding. The eighth pin (purple) is for receiving USB3 data (StdA_SSRX) with a minus sign. And finally, the last ninth is the same as the seventh, but with a plus sign.
How to wire a USB connector for charging?
Any charger uses only two wires from the USB connector: + 5V and a common contact. Therefore, if you need to solder a USB 2.0 or 3.0 type connector to the “charging”, then you should use the first and fourth pins. If you use mini or micro types, then you need to solder to the first and fifth pins. The most important thing when applying supply voltage is to maintain the polarity of the device.
Most modern mobile phones, smartphones, tablets and other wearable gadgets support charging via a mini-USB or micro-USB USB socket. True, a single standard is still far away and each company is trying to do the pinout in its own way. Probably they should buy the charger from her. It’s good that the USB plug and socket itself were made standard, as well as the supply voltage of 5 volts. So, having any charger adapter, you can theoretically charge any smartphone. How? and read on.
Pinout of USB connectors for Nokia, Philips, LG, Samsung, HTC
Brands Nokia, Philips, LG, Samsung, HTC and many other phones will recognize the charger only if the Data+ and Data- pins (2nd and 3rd) are shorted. You can short them in the USB_AF socket of the charger and easily charge your phone via 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. In this case, you solder the plus to 1 contact, and the minus to the 5th (last).
Pinout of USB connectors for iPhone
For iPhones, the Data+ (2) and Data- (3) contacts should be connected to the GND (4) contact through 50 kOhm resistors, and to the +5V contact through 75 kOhm resistors.
Samsung Galaxy charging connector pinout
To charge the Samsung Galaxy, a 200 kOhm resistor must be installed in the USB micro-BM plug between pins 4 and 5 and a jumper between pins 2 and 3.
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 via cable, you need to short-circuit pins 4 and 5 of the mini-USB plug. To recharge, you need to connect pins 4 and 5 through an 18 kOhm resistor.
Pinout diagrams for charging tablets
Almost any tablet computer requires a large current to charge - 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 provide more than 0.9 amperes. Therefore, a separate nest (often round type) is placed. But it can also be adapted to a powerful USB power source if you solder an adapter like this.
Pinout of the charging socket of the Samsung Galaxy Tab tablet
To properly charge the Samsung Galaxy Tab tablet, they recommend another circuit: two resistors: 33 kOhm between +5 and jumper D-D+; 10 kOhm between GND and jumper D-D+.
Pinout of charging port connectors
Here are several diagrams of the voltages on the USB contacts, indicating the values of the resistors that allow these voltages to be obtained. Where a resistance of 200 Ohms is indicated, you need to install a jumper whose resistance 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 identification 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 is declared in Host mode (with connection to PD peripherals - USB-Hub, mouse, keyboard, HDD and with the possibility of additional power supply), for some devices - with the ability to charge PD during an OTG session .
How to remake a plug with your own hands
Now you have a pinout diagram for all popular smartphones and tablets, so if you have the skill to work with a soldering iron, there will be no problems converting any standard USB connector to the type your device needs. Any standard charging that is based on the use of USB involves the use of only two wires - +5V and a common (negative) contact.
Just take any 220V/5V charging adapter and cut off the USB connector from it. The cut end is completely freed from the shield while the remaining four wires are stripped and tinned. Now we take a cable with a USB connector of the desired type, after which we also cut off the excess from it and carry out the same procedure. Now all that remains is to simply solder the wires together according to the diagram, after which each connection is insulated separately. The resulting case is wrapped on top with electrical tape or tape. You can fill it with hot glue - also a normal option.
Bonus: all other connectors (sockets) for mobile phones and their pinouts are available in a single large table -.
A little history of USB
The development of the Universal Serial Bus or USB began in 1994 by Indian-American engineer Ajay Bhatt of Intel and his division of specialists from leading computer companies called USB-IF (USB Implementers Forum, Inc). The company developing the port included representatives from Intel, Compaq, Microsoft, Apple, LSI and Hewlett-Packard. The developers were faced with the task of inventing a port that was universal for most devices, working on the Plug&Play principle, when the device, after connecting to the computer, either started working immediately or started after installing the necessary software (drivers). The new principle should replace the LPT and COM port, and the data transfer rate should be at least 115 kbit/s. In addition, the port had to be parallel, to organize the connection of several sources to it, and also allow the use of “hot” connection of devices without turning off or rebooting the PC.
The first non-industrial sample of a USB port coded 1.0 with the ability to transfer data up to 12 Mbit/s. was introduced in late 1995 - early 1996. In mid-1998, the port was updated with automatic speed maintenance for a stable connection and could operate at a speed of 1.5 Mbit/s. Its modification became USB 1.1. Starting in mid-1997, the first motherboards and devices with this connector were released. In 2000, USB 2.0 appeared, supporting speeds of 480 Mbit/s. The main design principle is the ability to connect older USB 1.1 devices to the port. At the same time, the first 8 megabyte flash drive for this port appeared. 2008, with improvements to the USB controller in terms of speed and power, was marked by the release of the 3rd version of the port, supporting data transfer at speeds of up to 4.8 Gbit/s.
Basic concepts and abbreviations used when pinouting USB connectors
VCC (Voltage at the Common Collector) or Vbus– positive potential contact of the power supply. For USB devices it is +5 Volts. In radioelectric circuits, this abbreviation corresponds to the supply voltage of bipolar NPN and PNP transistors.
GND (Ground) or GND_DRAIN– negative power contact. In equipment (including motherboards) it is connected to the housing to protect against static electricity and sources of external electromagnetic interference.
D- (Data -)- information contact with zero potential, relative to which data transfer occurs.
D+ (Data+)– information contact with logical “1”, necessary for data transfer from the host (PC) to the device and vice versa. Physically, the process is the transmission of positive rectangular pulses of different duty cycles and an amplitude of +5 Volts.
![](https://i2.wp.com/elektronika-muk.ru/img/raspinovka-usb-razemov-2.jpg)
Male– USB connector plug, popularly referred to as “male”.
Female– USB connector or female.
Series A, Series B, mini USB, micro-A, micro-B, USB 3.0– various modifications of USB device connectors.
RX (receive)– data reception.
TX (transmit)– data transfer.
-StdA_SSRX– negative contact for receiving data in USB 3.0 in SuperSpeed mode.
+StdA_SSRX– positive contact for receiving data in USB 3.0 in SuperSpeed mode.
-StdA_SSTX– negative contact for data transfer to USB 3.0 in SuperSpeed mode.
+StdA_SSTX– positive contact for data transfer to USB 3.0 in SuperSpeed mode.
DPWR– additional power connector for USB 3.0 devices.
USB connector pinout
For specifications 1.x and 2.0, the pinout of the USB connector is identical.
![](https://i0.wp.com/elektronika-muk.ru/img/raspinovka-usb-razemov-3.jpg)
As we can see from the figure, on legs 1 and 4 there is supply voltage for the periphery of the connected device, and information data is transmitted through contacts 2 and 3. If you are using a five-pin micro-USB connector, please refer to the following figure.
![](https://i1.wp.com/elektronika-muk.ru/img/raspinovka-usb-razemov-4.jpg)
As you can see, the use of 4 pins is not provided for in the standard specification. However, sometimes pin 4 is used to supply positive power to the device. Most often, these are energy-intensive consumers with a current tending to the maximum permissible for a USB 2.0 connector, as will be discussed below. According to the standard, each wire has its own color. So the positive power contact is connected by a red wire, the negative one by a black wire, the data- signal goes along white, and the positive information signal data+ goes through green. In addition, to protect devices from external influences, high-quality cables use shielding of the metal parts of the connectors by shorting the outer metallized cable braid to the housing. In other words, the cable shield can be connected to the negative power supply of the connector (but this condition is not necessary). Using a shield allows you to improve the stability of data transmission, increase speed and apply a longer cable length to the device.
![](https://i0.wp.com/elektronika-muk.ru/img/raspinovka-usb-razemov-5.jpg)
If you use a micro-USB – OTG cable to the tablet, the 4th unused contact is connected to the negative wire. The cable diagram is clearly presented in the figure from 4pda.ru. In this case, it is strictly forbidden to supply positive power to the 4th pin of the connector, which will result in failure of either the USB port controller or failure of the OTG controller!
As for the USB 2.0 connector specification, below is a table of the main characteristics.
The specification also indicates that to filter the useful signal, the maximum capacitance between the Data bus and the negative power contact (ground) can be used with a capacitance of up to 10uF (minimum 1uF). It is not recommended to use a higher capacitor value, since at speeds close to the maximum, the pulse fronts are delayed, which leads to a loss of speed characteristics of the USB port.
![](https://i2.wp.com/elektronika-muk.ru/img/raspinovka-usb-razemov-6.jpg)
When connecting external connectors of USB ports to the motherboard, you should pay special attention to the correct connection of the wires, since it is not as dangerous to confuse the Data - and Data + information signals as it is dangerous to swap the power wires. In this case, from the experience of repairing electronic equipment, the connected device often becomes unusable! The connection diagram must be looked at in the instructions for the motherboard.
It remains to add that for the implementation of cables for connected devices of the USB 2.0 connector, a standard for the cross-section of each wire in the cord has been approved.
AWG is the American wire gauge marking system.
Now let's move on to the USB 3.0 port
The second name for a USB 3.0 port is USB Super Speed, due to the increased data transfer speed of up to 5 Gb/sec. To increase speed indicators, engineers used full-duplex (two-wire) transmission of both sent and received data. Due to this, 4 additional contacts appeared in the connector -/+ StdA_SSRX and -/+StdA_SSTX. In addition, increased speeds required the use of a new type of controller with higher power consumption, which led to the need to use additional power pins in the USB 3.0 connector (DPWR and DGND). The new type of connector began to be called USB Powered B. In a digression, let’s say that the first Chinese flash drives for this connector were made in cases without taking into account the thermal characteristics of their controllers and, as a result, got very hot and failed.
The practical implementation of the USB 3.0 port made it possible to achieve a data exchange rate of 380 MB/sec. For comparison, the SATA II port (connecting hard drives) is capable of transferring data at a speed of 250 MB/sec. The use of additional power allowed the use of devices with a maximum current consumption of up to 900mA on the socket. This way, either one device or up to 6 gadgets with a consumption of 150mA can be connected. In this case, the minimum operating voltage of the connected device can be reduced to 4V. Due to the increase in connector power, engineers had to limit the length of the USB 3.0 cable to 3 m, which is an undoubted disadvantage of this port. Below we provide the standard USB 3.0 port specification
The pinout of the USB 3.0 connector is as follows:
![](https://i2.wp.com/elektronika-muk.ru/img/raspinovka-usb-razemov-7.jpg)
![](https://i0.wp.com/elektronika-muk.ru/img/raspinovka-usb-razemov-8.jpg)
Operating systems starting with Windows 8, MacBook Air and MacBook Pro latest versions and Linux with kernel version 2.6.31 have full software support for the USB 3.0 specification. Due to the use of two additional power contacts in the USB 3.0 Powered-B connector, it is possible to connect devices with a load capacity of up to 1A.
In this article I will tell you how to properly solder a micro USB plug on a tablet without damaging it. They often brought tablets to me for repair with this problem, they tore out the micro USB by the “root”, touched the cord naked when it was lying on charge or for some other reason. The tablet is a fragile device and must be handled with care and precision, that’s what I tell my clients. So we brought you a tablet with a torn plug or when it has not yet been completely torn off, we carefully disassemble it, basically the bottom cover of the tablet is attached to plastic so-called latches and usually it is screwed on with several small bolts.
After making sure that all the screws are unscrewed, we take a scalpel or a knife with a thin blade and carefully pry the cover around the entire perimeter of the slot, gently turning the blade upward towards the cover, thereby releasing the plastic latches from the grooves of the tablet body. This must be done with minimal effort, remember if the clamps do not release with a little force, it means you are doing something wrong, it is better to calmly and slowly try to understand the principle of fixing the clips and in which direction you need to turn the scalpel blade. Believe me, if disassembly is unsuccessful, it is very difficult to restore the fastening in the future; you will have to glue the fasteners if you still collect small plastic fragments.
Let's say you managed to carefully remove the cover, then you need to unsolder the battery that is inside, you need to unsolder the terminals since you will not be able to turn the board over and get to the micro USB plug, and you also need to unsolder the terminals from the battery in order not to accidentally short-circuit something and do not damage your tablet. So, we unsoldered the battery terminals and unscrewed all the fastening screws of the board itself, then we turn it over. I would like to note that if the cables between the main board and the screen allow you to turn the board over, then it is advisable not to touch the cable.
Now let’s move directly to our micro USB connector, arm ourselves with a magnifying glass and carefully examine the plug itself and the track pins that fit into it; if the tracks are intact and have not peeled off, then this is very good. Take a soldering iron of no more than 25 watts and clean the track pins on the board, where the plug itself used to be. There should be five conclusions. Next, take the plug and glue it to the board with super glue, you only need a little glue, it’s better to take a match and dip it in the glue, then
distribute it evenly over the entire bottom surface of the plug. Then, when the glue dries a little, you can solder the pins between the board and micro USB. But if the leads of the tracks are torn off on the board, then you can try to do this: first, you need to use a magnifying glass to find all the ends of the tracks, if possible, and clean their ends from varnish and tin, but keep in mind that in no case should you overheat, and then We also glue the plug and solder the leads between the connector and the tracks using thin wires.
If, for example, it is not possible to restore all the tracks on the board, then you can try to at least simply charge the tablet’s battery, for this you will need to solder only two pins, plus and minus, they are located on the first and last plug, pay attention to the figure, I indicated them arrow. But in this situation, you will not be able to connect your tablet to a computer or to an external USB modem or Flash memory. That's all, I wish you success. You can read detailed information on my website, and also see screenshots of disassembling the tablet. Available: books, reference books, magazines, diagrams. radiorodot
Today, almost all modern and not only devices are equipped with USB connectors. A broken USB connector is a common problem that occurs due to accidental mechanical damage, such as damage during charging. If you are faced with such a problem, then this article will definitely help you.
To re-solder a USB connector yourself, you will need some tools, such as:
- any soldering iron with a power of 25 watts,
- tweezers,
- easily fusible tin,
- solder,
- small shaped screwdriver,
- scalpel or knife with a thin blade,
- magnifying glass
Below we will take a step-by-step look at how to disassemble your device. The most important thing is to do everything extremely carefully.
Firstly, you need to unscrew all the mounting screws on your device. First, release the back cover by prying it open with a thin blade. With this we release the housing latches from the grooves by tilting the knife towards the screen.
Secondly, after removing the cover on the device, be sure to ground your soldering iron. Then solder the wire to the common body, and then the other end of the wire to the body of the soldering iron itself. These actions are necessary in order to protect the gadget from accidental static electricity, which can damage its electronic components. You also need to make an antistatic wrist strap and ground it too.
Thirdly In order not to inadvertently short-circuit the electronic circuit and damage the components, you need to unsolder the wires from the battery.
And finally, we unscrew all the fastening screws on the board and turn it over, thereby we will get directly to the micro usb connector itself.
As you understand, DIY repairs can be quite problematic. Re-soldering micro usb is not an easy task for the average user. If you don’t want to take risks, then bring your device to us, at Smartkit, and we will be happy to solve your problem for a low price and quickly.