USB (Universal Serial Bus- “universal serial bus”) - a serial data transfer interface for medium- and low-speed peripheral devices. A 4-wire cable is used for connection, with two wires used to receive and transmit data, and 2 wires to power the peripheral device. Thanks to the built-in USB power lines allows you to connect peripheral devices without its own power supply.

USB Basics

USB cable consists of 4 copper conductors - 2 power conductors and 2 data conductors in twisted pair, and a grounded braid (screen).USB cables have physically different tips “to the device” and “to the host”. It is possible to implement a USB device without a cable, with a “to-host” tip built into the housing. It is also possible to permanently integrate the cable into the device(for example, USB keyboard, Web camera, USB mouse), although the standard prohibits this for full and high speed devices.

USB bus strictly oriented, i.e. it has the concept of “main device” (host, also known as a USB controller, usually built into the south bridge chip on the motherboard) and “peripheral devices”.

Devices can receive +5 V power from the bus, but may also require an external power supply. A standby mode is also supported for devices and splitters upon command from the bus, removing the main power while maintaining standby power and turning it on upon command from the bus.

USB supportsHot plugging and unplugging of devices. This is possible due to the increase in the length of the grounding contact conductor in relation to the signal ones. When connected USB connector are the first to close grounding contacts, the potentials of the housings of the two devices become equal and further connection of the signal conductors does not lead to overvoltages, even if the devices are powered from different phases of a three-phase power network.

At the logical level, a USB device supports data transfer and reception transactions. Each packet of each transaction contains a number endpoint on the device. When a device is connected, drivers in the OS kernel read a list of endpoints from the device and create control data structures to communicate with each endpoint on the device. The collection of endpoints and data structures in the OS kernel is called pipe.

Endpoints, and therefore channels, belong to one of 4 classes:

• continuous (bulk),
• manager (control),
• isochronous (isoch),
• interrupt.

Low speed devices such as a mouse cannot have isochronous and flow channels.

Control channel designed for exchanging short question-answer packets with the device. Any device has control channel 0, which allows the OS software to read brief information about the device, including manufacturer and model codes used to select a driver, and a list of other endpoints.

Interrupt channel allows you to deliver short packets in both directions, without receiving a response/confirmation, but with a guarantee of delivery time - the packet will be delivered no later than in N milliseconds. For example, used in input devices (keyboards, mice or joysticks).

Isochronous channel allows you to deliver packets without a guarantee of delivery and without replies/confirmations, but with a guaranteed delivery speed of N packets per bus period (1 KHz for low and full speed, 8 KHz for high speed). Used to transmit audio and video information.

Flow channel provides a guarantee of delivery of each packet, supports automatic suspension of data transmission due to device reluctance (buffer overflow or underrun), but does not guarantee delivery speed and delay. Used, for example, in printers and scanners.

Bus time is divided into periods, at the beginning of the period the controller transmits the “beginning of period” packet to the entire bus. Then, during the period, interrupt packets are transmitted, then isochronous ones in the required quantity; for the remaining time in the period, control packets are transmitted, and lastly, stream packets.

Active side of the bus is always the controller, the transfer of a data packet from the device to the controller is implemented as a short question from the controller and a long response from the device containing data. The packet movement schedule for each bus period is created jointly by the controller hardware and driver software; for this, many controllers use Direct Memory Access DMA (Direct Memory Access) - mode of data exchange between devices or between the device and the main memory, without the participation of the Central Processor (CPU). As a result, the transfer speed is increased since data is not sent back and forth to the CPU.

The packet size for an endpoint is a constant built into the device's endpoint table and cannot be changed. It is selected by the device developer from among those supported by the USB standard.

USB Specifications

Features, advantages and disadvantages of USB:

• High transfer speed (full-speed signaling bit rate) - 12 Mb/s;
• The maximum cable length for high transfer speed is 5 m;
• Low-speed signaling bit rate - 1.5 Mb/s;
• The maximum cable length for low communication speed is 3 m;
• Maximum connected devices (including multipliers) - 127;
• It is possible to connect devices with different baud rates;
• There is no need to install additional elements such as terminators;
• Supply voltage for peripheral devices - 5 V;
• The maximum current consumption per device is 500 mA.

USB signals are transmitted over two wires of a shielded 4-wire cable.

USB 1.0 and USB 2.0 connector pinout

Type A		Type B
Fork (on cable)	Socket (on the computer)	Fork (on cable)	Socket (on peripheral device)

Names and functional assignments of USB 1.0 and USB 2.0 pins

Data 4 GND Ground (body)

Disadvantages of USB 2.0

At least the maximum USB 2.0 data transfer rate is 480 Mbit/s (60 MB/s), in real life it is unrealistic to achieve such speeds (~33.5 MB/s in practice). This is due to the large delays on the USB bus between the request for data transfer and the actual start of the transfer. For example, FireWire, although it has a lower peak throughput of 400 Mbps, which is 80 Mbps (10 MB/s) less than USB 2.0, actually allows for greater data transfer throughput to hard drives and other storage devices. In this regard, various mobile drives have long been limited by the insufficient practical bandwidth of USB 2.0.

UBS connectors are the most common types of connectors that are used to connect various types of digital electronic devices.

We are sure that everyone in the house has a lot of cables with such connectors, because they are used to connect peripheral devices to a computer: mice, joysticks, printers, scanners, external hard drives and much more.

In contact with

Also, when you purchase a mobile phone, you receive connectors included with it to connect the gadget to a computer and a charger.

Pinout concept

Sometimes it happens that due to a broken connector or cable break, it stops working. charger phone device or anything connected to a computer. For a person who does not have the skill to work with a soldering iron, this is an unpleasant surprise and a problem.

But, for a person who is familiar with the basics of electronics and knows how to solder, the problem is solved simply - a new connector is soldered or the old one is soldered, and our favorite devices function again.

However, before you start repairing, you need to know USB connector pinout – arrangement of wires by color in relation to the connector contacts. Incorrect wiring will lead to failure of the connected gadgets.

General information about USB connectors

USB (Universal Serial Bus)– a data transfer standard that was developed in 1994 to organize an interface between a computer and peripheral devices.

Now it is used both to transfer data between digital devices and to charge the batteries of a passive device from an active, so-called “host”. An example would be charging a phone from a computer.

Connectors are divided into three types:

The first type is usb 1.1

It was developed as one of the first to expand the functionality of a computer and made it possible to connect additional devices to the computer, including mobile phones for transmitting speech in digital form.

Due to the fact that the data transfer speed was low, it was replaced by usb 2.0. Currently, usb 1.1 is considered obsolete and is practically not used.

The second type is usb 2.0

The most common at the moment and widely used. Most electronic devices sold in electronics stores have USB 2.0 connectors, despite the fact that they no longer fully meet modern transfer speed requirements. In particular, hard drives can read information at a speed 3-4 times higher than the speed provided by this type of device. However, they remain common due to the fact that this speed is quite suitable for the operation of mice, keyboards and other devices.

The third type is usb 3.0

It is a new generation of devices, the transfer speed of which satisfies the fastest hard drives and provides a speed reserve for the future. Connectors of this type are specially marked in blue.

All connectors of the considered types have design differences, which can be determined by the designation:

Letters F and M in usb marking connectors mean:

• F (female) – female-type connector;
• M (male) – male type connector.

Mini-usb, and later micro-usb, were developed to connect to portable and mobile devices.

Connectors of the mini-AB and micro-AB types serve as adapters for connecting mini A and mini B, micro-A and micro-B to each other.

Connector pinout

The USB 2.0 connector pinout is as follows:

• Red wire soldered to pin 1 of the connector: +5V power is supplied;
• White wire– to contact 2: information (D -);
• Green wire– to pin 3: information (D +);
• Black wire– to pin 4: common.

Mini and micro USB cables have five wires of different colors and a five-pin connector. The difference between the wiring of such micro connectors and the wiring of a USB 2.0 connector is as follows:

• wiring of the first three contacts is similar to usb 2.0;
• the lilac wire goes to pin 4 - this is ID; in connectors A – not used, in connectors B – connected to the body;
• The black wire goes to pin 5 – common.

USB 3.0 connector pinout is done as follows:

• The wiring of the first 4 contacts is identical to the wiring of the USB 2.0 connector;
• the blue wire goes to pin 5 – transfer of information with a plus sign;
• yellow wire – to pin 6 – transfer of information with a minus sign;
• additional housing - to pin 7;
• purple wire – to pin 8 – transfer of information with a minus sign;
• orange wire - to pin 9 - transfer of information with a plus sign.

Micro and mini usb for mobile phones

All modern mobile phones are charged via mini and micro connectors from own charger. We discussed the pinout of mini and micro connectors above.

Now let’s talk about why it happens that the charger seems to be suitable in terms of its parameters (voltage and charging current), and the connector from your phone fits well into it, but the charger is not “native” - and charging does not occur. Why?

The point is in some differences in the pinout of mini and micro connectors of phones inserted into the charger.

For example, gadgets such as HTC, Philips, Samsung, as well as Nokia and LG recognize the charger as theirs if Pins 2 and 3 in the connector are shorted. By connecting these contacts in the AF connector of the charging device, it is quite possible to use it to charge these types of phones.

Motorola devices will “require” the installation of a resistor with a nominal value of 200 kiloOhms between pins 4 and 5. Without him The device charges very slowly.

Summarizing what has been said, we can conclude that when repairing cables for your favorite gadgets, it is important to know the pinout of the connectors in order to properly wire the cable wires, and then your electronic “friends” will serve you for a long time.

The technological process does not stand still. Modern models of various digital devices are strikingly different from their older counterparts. Not only their appearance and internal equipment have changed, but also the methods of connecting to computers and chargers. If only 5-7 years ago many phones and even cameras did not have this capability. But at the moment, absolutely every digital device can be connected to a personal computer or laptop. Phone, player, smartphone, tablet, video camera, player or camera - they are all equipped with connectors that allow you to connect them to other devices.

But, as you can easily see, the connector is different. And for some reason the cord purchased with the phone cannot be used with your favorite player. As a result, a bunch of cables accumulate, you constantly get confused in them and cannot understand why it was impossible to make one wire suitable for connecting all devices. But, as we know, this does not happen. Although now there is a more or less standard connector, at least for smartphones, phones and tablets. And its name is micro-USB. What kind of miracle this is and how it works, we will tell you below.

Micro USB connector: what is it?

The two most popular connectors lately are mini and micro-USB. Their names speak for themselves. These are smaller, more practical designs that are used on smaller digital devices to save space and perhaps create a sleeker appearance. For example, a micro-USB connector for a tablet is almost 4 times smaller than a standard USB 2.0, and considering that the device itself is several times smaller than a personal computer or even a laptop, this option is simply ideal. But there are also some nuances here. For example, more can never be made into less, so micro-USB connectors cannot even be replaced with mini-USB. Although in some cases the reverse process is acceptable. And replacing a micro-USB with your own hands is unlikely to end in anything good. This is such a piece of jewelry work. In addition, the word “micro” covers several types of connectors, and you need to remember this. Especially if you are trying to buy a new wire. Your tablet's micro USB may not be compatible with the connector on the end of the cable you purchased.

Varieties

Micro-USB connectors can be of two completely different types. They have different areas of application and, accordingly, they look different. The first type is called micro-USB 2.0. type B - it is used in devices by default and is an unspoken standard for the latest models of smartphones and tablets, because of this it is very common and almost every person at home has at least one micro-USB 2.0 cable. type B.

The second type is micro-USB 3.0 - these connectors are not installed on tablets, but can be found on smartphones and phones of some brands. Most often they are used to equip external hard drives.

Advantages

The main advantages of micro-USB connectors for tablets include increased density and reliability of the plug. But this fact does not exclude the possibility of problems with these components. Most often, the cause of breakdown is the carelessness of the owners of digital devices themselves. Sudden movements, tablets and phones falling onto the floor or even asphalt, especially on the side where the connector itself is located, attempts to correct something with your own hands without the appropriate knowledge - these are the main reasons why even the most durable parts of USB ports fail out of service. But it happens that this happens due to wear and tear of the device, improper operation or manufacturing defects.

Most often, the cause of malfunction is either the micro-USB connectors themselves, or the parts adjacent to them and connected to them in a circuit. For any experienced craftsman, replacing it is a matter of minutes, but not everyone can cope with this at home. If you are still interested in how you can repair a micro-USB connector yourself, pinouting (or, in other words, desoldering) is not the longest or most complicated process if you approach it wisely and first read the relevant information. Some tips will be given below.

Micro USB connector: pinout

As you know, with ordinary ports and connectors everything is simple - you just need to take an image of the front part of their connector, but in a mirror image, and solder it. With USB mini- and micro-types everything is a little different. Their connectors contain 5 contacts, but on connectors of type B, contact number 4 is not used, and on type A it is closed to GND, which occupies the fifth place.

Functions of the “legs” of the micro-USB connector

Since most modern tablets have micro-USB, which serves not only for charging, but also for synchronization, problems with it arise more often due to the more frequent use of the connector.

So, as mentioned above, a regular micro-USB connector has five “legs”. One is positive, at five volts, and one is negative. They are located on different sides of the connector and, accordingly, suffer less when separated from the motherboard. Only one “leg” of the connector, which more often than others is pulled out of the contact pad, is subject to more wear. It is located closer to the minus “leg”. If this contact is damaged, the device cannot be charged. That is, the system can see the power supply, but the charging process will not occur.

The remaining two “legs” are responsible for synchronization, that is, for the ability to upload and download photos, music, etc. They do this at the same time, so the separation of one will entail the cessation of the work of the second.

Knowing the functions of the “legs”, you will be able to determine which contacts are causing you to have problems and which of them you will need to solder to get your tablet back into operation.

Consequences of incorrect connector replacement

Having soldered micro-USB incorrectly, owners most often encounter the following problems:

1. Short circuits of the power supply if they are soldered inverted type.
2. The tablet detects the charging cord, but the battery does not charge.
3. The tablet's battery charges perfectly, but it does not sync with a laptop or computer.
4. The tablet works fine, but sometimes it “reminds” you that you should take it to a workshop instead of soldering it yourself (for example, charging does not start immediately after turning it on, or sometimes the cord needs to be pulled out and reinserted several times before charging starts).

The Future of Micro USB

Since these are some of the most popular ports today, if you learn how to change them once, this skill will help you out very often in the future. And let them not be accepted as the “gold standard” in the development of phones and other digital devices. And we still have to have a whole collection of wires specifically for an Acer laptop, for a Samsung phone, for an Apple iPad and a Nikon camera, but the active use of micro-connectors gives us hope that soon instead of a “bouquet” we will have one on our shelf micro-USB cable suitable for at least 90% of the equipment in the house.

What types of USB connectors and plugs are there?

Due to the fact that there are quite a lot of USB connectors, there is often confusion between them. Sometimes, after purchasing a cable, a wave of disappointment sets in, because it may turn out that the plug of the purchased wire does not fit the device. Therefore, in this article I will try to tell you what types of connectors USB cables have.

Despite the fact that there is a lot of information on this topic on the Internet, it usually touches on development issues, gives dates of approval and commissioning, design features and pinouts. In general, more background information is provided, which is usually not of particular interest to the end user. I will try to consider connectors from a household point of view - where they are used, their advantages and disadvantages, differences and features.

USB versions. What is the difference between USB 2.0 and USB 3.0

Let's start with some general information. USB devices come in three versions - 1.1, 2.0 and 3.0. The first is almost never used, since it provides too low data transfer speed (12 Mbit - approximately 1.2 MB / s) and can be used exclusively for compatibility with finicky hardware. The second version now occupies a dominant position. Most devices sold in stores and currently in use support the second version. It provides a throughput of 480 Mbit/s, that is, the copy speed should theoretically be at the level of 48 MB/s. However, due to design features and less than ideal implementation in practice, the speed rarely exceeds 30-33 MB/s. Most external hard drives can read at 3-4 times faster speeds. That is, this connector is a bottleneck that slows down the operation of modern drives. For mice, keyboards, etc., speed does not matter.

The third version is colored blue, indicating that it belongs to the last generation. The bandwidth is 5 Gbps, which can give 500 MB/s. Modern hard drives have a speed of about 150-170 MB/s, that is, the third version of USB will be able to provide a large speed reserve for the coming years.

Compatible with different USB versions.

A few words about compatibility. Versions 1.1 and 2.0 are structurally fully compatible with each other. If one of the connected sides is an older version, then the work will be carried out at a reduced speed, and the operating system will display the message “The device can work faster,” which means that there is a fast USB 2.0 port on the computer, but the device that is plugged into it is slow - version 1.1.

But with the compatibility of USB versions 2.0 and 3.0, not everything is so simple. Any USB 2.0 device or cable can be connected to the blue port of version 3. But the opposite cannot be done. Modern cables and devices with USB 3.0 differ from the usual connectors in that they have additional contacts that increase the interface bandwidth, so you won’t be able to connect them to the old port (the only exception is type A).

USB power

Any USB connector supplies a voltage of 5 Volts, and the current cannot exceed 0.5 Amperes (for USB 3.0 - 0.9 Amperes). In practice, this means that the maximum power of the connected device can be no more than 2.5 Watts (4.5 for USB 3.0). Therefore, there will be no problems when connecting low-power and portable devices - players, phones, flash drives and memory cards. But all large-sized and massive equipment has external power supply from the network.

Now let's move on to the types of connectors. I will not consider completely exotic options, but will only talk about the most popular and frequently used plugs. Affiliation with a specific USB version will be indicated in brackets.

USB type A (USB 2.0)

This is the most common and most recognizable connector currently existing. Most devices connected via USB have it. Mice, flash drives, keyboards, cameras and more - they all feature USB Type A, which dates back to the 90s. One of the most important advantages of this port is reliability. It can survive a fairly large number of connections, does not fall apart, and has truly deserved to become the most common means of connecting everything possible. Despite its rectangular shape, it cannot be stuck in with the reverse side; there is “fool protection”. However, it is not suitable for portable devices, since it has quite large dimensions, which ultimately led to the appearance of smaller modifications.

USB type B (USB 2.0)

The second type of USB has gained much less fame than its relative. Unlike type A plugs, which have a rectangular shape, all modifications of type B (including Mini and Micro - see below) usually have either a square or trapezoidal shape. The regular, full-size type B is the only representative that has a square shape. It is quite large in size and for this reason it is used in various peripherals and large stationary devices - printers, scanners, and sometimes ADSL modems. Interestingly, printer manufacturers rarely include such a cable in their products, so the cord for the printing device or MFP must be purchased separately.

Mini USB Type B (USB 2.0)

The emergence of a huge number of miniature devices has led to the emergence of tiny USB connectors. And Mini USB type B truly became widespread with the advent of portable hard drives, in which it is widely used. The connector has five contacts, not 4 like “adult plugs”, although one of them is not used. Unfortunately, miniaturization has had a negative impact on reliability. Despite its long service life, after a while the Mini USB becomes loose and begins to wobble, although it does not fall out of the port. Currently, it continues to be actively used in players, portable hard drives, card readers and other small-sized equipment. It is interesting that the second modification (type A) is almost never used; you will hardly find such a cord on sale. It is gradually beginning to be replaced by a more advanced modification of Micro USB.

Micro USB type B (USB 2.0)

A modified version of the previous connector. It has very miniature dimensions, as a result of which it is used by manufacturers in modern technology, which is characterized by its small thickness. In addition, the fastening has been improved; the plug fits very tightly and does not fall out. In 2011, this connector was approved as a unified standard for charging phones, smartphones, tablets, players and other portable electronics. Therefore, with just one cord, you can feed the entire “electronic zoo”. The standard continues to gain momentum, one can hope that in a year or two almost all new devices will be equipped with a single connector. As in the previous case, type A is almost never used.

USB type A (USB 3.0)

New USB standard with significantly higher bandwidth. The appearance of additional contacts has led to a change in the appearance of almost all USB 3.0 plugs. Despite this, type A has remained unchanged in appearance, only the blue color of the core indicates that it is a newcomer. This means that backward compatibility is maintained. A USB 3.0 device can be plugged into an old USB 2.0 port and vice versa. This is the main difference from other USB 3.0 connectors. Such ports can be found in modern computers or laptops.

USB type B (USB 3.0)

By analogy with the previous version, this type is used in medium and large peripherals and devices that require high performance - NAS, stationary hard drives. The connector is heavily modified and cannot be connected to USB 2.0. You also rarely see such cords on sale (in contrast to the previous one). Plugging such a connector into a USB 2.0 type B will no longer work - the top part will get in the way.

Micro USB (USB 3.0)

This connector continues the traditions of the “classic” Micro USB. It has the same qualities - compactness, reliability, good connection, but at the same time it has a high data transfer speed. Therefore, it is mainly used in new external ultra-fast hard drives and SSDs. It is becoming more and more popular, so in order not to carry a cable with an external hard drive, you can buy an additional cable at any store. The main part of the connector completely copies Micro USB of the second revision

The main thing is not to confuse it - the difference between Micro USB and Mini USB.

The main confusion that arises among users is between Mini USB and Micro USB, which are indeed a bit similar. The first one is slightly larger, and the second one has special latches on the back side. It is by the latches that you can always distinguish these two connectors. Otherwise they are identical. And since there are a lot of devices with both, it is better to have both cables - then there will be no problems connecting any modern portable equipment.

Mini USB on the left, Micro USB on the right.
Mini USB is much thicker, which makes it impossible to use
it in compact thin devices.
Micro USB is easy to recognize by its two notches,
holding the plug firmly when connecting.

Three brothers of the same family.
Mini USB and Micro USB are much thinner than usual.
On the other hand, the “crumbs” lose
in the reliability of an older comrade.

The USB interface began to be widely used about 20 years ago, to be precise, since the spring of 1997. It was then that the universal serial bus was implemented in hardware in many personal computer motherboards. Currently, this type of connecting peripherals to a PC is a standard, versions have been released that have significantly increased the data exchange speed, and new types of connectors have appeared. Let's try to understand the specifications, pinouts and other features of USB.

What are the advantages of Universal Serial Bus?

The introduction of this connection method made it possible:

• Quickly connect various peripheral devices to your PC, from the keyboard to external disk drives.
• Make full use of Plug&Play technology, which simplifies the connection and configuration of peripherals.
• Refusal of a number of outdated interfaces, which had a positive impact on the functionality of computing systems.
• The bus allows not only to transfer data, but also to supply power to connected devices, with a load current limit of 0.5 and 0.9 A for the old and new generations. This made it possible to use USB to charge phones, as well as connect various gadgets (mini fans, lights, etc.).
• It has become possible to manufacture mobile controllers, for example, a USB RJ-45 network card, electronic keys for entering and exiting the system

Types of USB connectors - main differences and features

There are three specifications (versions) of this type of connection that are partially compatible with each other:

1. The very first version that has become widespread is v 1. It is an improved modification of the previous version (1.0), which practically did not leave the prototype phase due to serious errors in the data transfer protocol. This specification has the following characteristics:

• Dual-mode data transfer at high and low speed (12.0 and 1.50 Mbps, respectively).
• Possibility of connecting more than a hundred different devices (including hubs).
• The maximum cord length is 3.0 and 5.0 m for high and low transfer speeds, respectively.
• The rated bus voltage is 5.0 V, the permissible load current of the connected equipment is 0.5 A.

Today this standard is practically not used due to its low throughput.

1. The dominant second specification today... This standard is fully compatible with the previous modification. A distinctive feature is the presence of a high-speed data exchange protocol (up to 480.0 Mbit per second).

Due to full hardware compatibility with the younger version, peripheral devices of this standard can be connected to the previous modification. True, the throughput will decrease up to 35-40 times, and in some cases more.

Since these versions are fully compatible, their cables and connectors are identical.

Please note that, despite the bandwidth specified in the specification, the actual data exchange speed in the second generation is somewhat lower (about 30-35 MB per second). This is due to the implementation of the protocol, which leads to delays between data packets. Since modern drives have a read speed four times higher than the throughput of the second modification, that is, it does not meet current requirements.

1. The 3rd generation universal bus was developed specifically to solve problems of insufficient bandwidth. According to the specification, this modification is capable of exchanging information at a speed of 5.0 Gbit per second, which is almost three times the reading speed of modern drives. Plugs and sockets of the latest modification are usually marked blue to facilitate identification of belonging to this specification.

Another feature of the third generation is an increase in the rated current to 0.9 A, which allows you to power a number of devices and eliminate the need for separate power supplies for them.

As for compatibility with the previous version, it is partially implemented; this will be discussed in detail below.

Classification and pinout

Connectors are usually classified by type, there are only two of them:

Note that such convectors are compatible only between earlier modifications.

In addition, there are extension cables for the ports of this interface. At one end there is a type A plug, and at the other there is a socket for it, that is, in fact, a “female” - “male” connection. Such cords can be very useful, for example, to connect a flash drive without crawling under the table to the system unit.

Now let's look at how contacts are wired for each of the types listed above.

USB 2.0 connector pinout (types A and B)

Since the physical plugs and sockets of early versions 1.1 and 2.0 do not differ from each other, we will present the wiring of the latter.

Figure 6. Wiring the plug and socket of type A connector

Designation:

• A – nest.
• B – plug.
• 1 – power supply +5.0 V.
• 2 and 3 signal wires.
• 4 – mass.

In the figure, the coloring of the contacts is shown according to the colors of the wire, and corresponds to the accepted specification.

Now let's look at the wiring of the classic socket B.

Designation:

• A – plug connected to the socket on peripheral devices.
• B – socket on a peripheral device.
• 1 – power contact (+5 V).
• 2 and 3 – signal contacts.
• 4 – ground wire contact.

The colors of the contacts correspond to the accepted colors of the wires in the cord.

USB 3.0 pinout (types A and B)

In the third generation, peripheral devices are connected via 10 (9 if there is no shielding braid) wires; accordingly, the number of contacts is also increased. But they are located in such a way that it is possible to connect devices of earlier generations. That is, the +5.0 V contacts, GND, D+ and D-, are located in the same way as in the previous version. The wiring for Type A socket is shown in the figure below.

Figure 8. Pinout of Type A connector in USB 3.0

Designation:

• A – plug.
• B – nest.
• 1, 2, 3, 4 – connectors fully correspond to the pinout of the plug for version 2.0 (see B in Fig. 6), the colors of the wires also match.
• 5 (SS_TX-) and 6 (SS_TX+) connectors for data transmission wires via the SUPER_SPEED protocol.
• 7 – ground (GND) for signal wires.
• 8 (SS_RX-) and 9 (SS_RX+) connectors for data receiving wires using the SUPER_SPEED protocol.

The colors in the figure correspond to those generally accepted for this standard.

As mentioned above, a plug from an earlier model can be inserted into the socket of this port; accordingly, the throughput will decrease. As for the plug of the third generation of the universal bus, it is impossible to insert it into the sockets of the early release.

Now let's look at the pinout for the type B socket. Unlike the previous type, such a socket is incompatible with any plug of earlier versions.

Designations:

A and B are plug and socket, respectively.

Digital signatures for contacts correspond to the description in Figure 8.

The color is as close as possible to the color markings of the wires in the cord.

Micro USB connector pinout

To begin with, we present the wiring for this specification.

As can be seen from the figure, this is a 5 pin connection; both the plug (A) and socket (B) have four contacts. Their purpose and digital and color designation correspond to the accepted standard, which was given above.

Description of the micro USB connector for version 3.0.

For this connection, a characteristically shaped 10 pin connector is used. In fact, it consists of two parts of 5 pin each, and one of them fully corresponds to the previous version of the interface. This implementation is somewhat confusing, especially considering the incompatibility of these types. Probably, the developers planned to make it possible to work with connectors of earlier modifications, but subsequently abandoned this idea or have not yet implemented it.

The figure shows the pinout of the plug (A) and the appearance of the micro USB socket (B).

Contacts 1 to 5 fully correspond to the second generation micro connector, the purpose of the other contacts is as follows:

• 6 and 7 – data transmission via high-speed protocol (SS_TX- and SS_TX+, respectively).
• 8 – mass for high-speed information channels.
• 9 and 10 – data reception via high-speed protocol (SS_RX- and SS_RX+, respectively).

Mini USB pinout

This connection option is used only in early versions of the interface; in the third generation this type is not used.

As you can see, the wiring of the plug and socket is almost identical to the micro USB, respectively, the color scheme of the wires and the contact numbers are also the same. Actually, the differences are only in shape and size.

In this article we have presented only standard types of connections; many manufacturers of digital equipment practice introducing their own standards; there you can find connectors for 7 pin, 8 pin, etc. This introduces certain difficulties, especially when the question arises of finding a charger for a mobile phone. It should also be noted that manufacturers of such “exclusive” products are in no hurry to tell how the USB pinout is done in such contactors. But, as a rule, this information is easy to find on thematic forums.

USB cables have different physical ends. It depends on what device it is connected to. There are connections to the device itself and to the host. Moreover, USB can be with or without a cable. Another option is possible: the cable is built into the device itself. The cable is necessary to form an interface between the device and the host.

But after some time, the developers of such a computer interface as USB still had low speed in order to use external hard drives and other devices whose speed was much greater. Therefore, the creators of USB had to change the device so that a new model was obtained. Now the speed of the third type of USB has become ten times faster. Of course, this also affected charging.

General information about USB

The USB cable consists of four conductors made of copper. These are two conductors intended for power supply, and the remaining conductors are in a twisted pair. This kit also includes a grounded braid.

Let's now take a little look at the host. It acts as a special controller, which is programmed and controlled. Its task: to ensure the operation of the interface. By the way, the controller can most often be found in a microcircuit. A hub is required to connect the controller to other devices.

But in order to connect external devices to the hub, ports are used, at the end of which there are connectors. Cables help USB devices connect to ports. The device can be powered differently: from the bus or some kind of external power source.

It only takes a few minutes to get started and you can get started. At first the signal to start work is sent to the cable hub, which further informs that the equipment is ready for operation.

But it is worth remembering one rule. Whenever you start pinouting a device, first determine what the pinout is on your cable. The USB connector helps you connect all external devices to your computer. This modern connection method replaces all those methods that were previously available. Such connector provides additional options: When operating computer equipment, any devices can be connected and immediately put into operation. It may also affect the charging operation.

USB Specification

There were the first preliminary versions of USB, which began to be released in November 1994. This went on for a year. AND after that new USB models began to come out which are still in use today.

Today we can talk about the following models:

1. USB 1.0. This model was released in January 1996.
2. USB 1.1. This specification was released in September 1998.
3. USB 2.0. This model was released in 2000.

Technical characteristics of each model

The first model is USB 1.0. This specification distinguishes two operating modes:

1. Low bandwidth.
2. With high throughput.

The maximum cable length allowed in this model for the first operating mode is three meters, and for the second operating mode it reaches five meters. If you want to connect several devices, you can connect up to 127 of them.

The technical characteristics of the USB 1.1 model correspond to the first one, but all the problems and errors that arose during its use have been corrected. By the way, this is the first model that gained wide popularity and spread quickly.

The third model is USB 2.0. There are three operating modes for it, where mice, a joystick, gamepads, and a keyboard can be used, as well as video devices and devices that store information.

USB cables and connectors

Currently, there have been many different changes in the computer world. For example, a new interface has appeared with a modification of USB 3.0, its speed is ten times faster than the previous model. But There are other types of connectors, known as micro- and mini-USB. By the way, they can be found nowadays, for example, in tablets, phones, smartphones and in a wide variety of other computer products.

Each such bus, of course, also has its own wiring or pinout. It is necessary in order to then make an adapter at home, allowing you to switch from one type of connector to another. But this requires knowledge. For example, certain knowledge about how conductors are located. For example, you can charge any phone this way. If this work with the connectors is done incorrectly, then the device itself will be damaged.

There is a difference in the design of mini and macro devices. So, now they already have five contacts. And in a USB 2.0 device you can count nine pins. Therefore, the wiring of USB connectors in this model will proceed a little differently. The same pinout of USB connectors will be in modification 3.0.

Wiring will occur according to the following scheme: first, the red conductor, which is responsible for supplying the voltage that powers the current. Then comes the white and green conductor, whose task is to transmit information. Then you should go to the black conductor, which receives the supply of zero voltage that is supplied.

In the USB 3.0 design, the wires are arranged completely differently. The first four of them are similar in their connector to the 2.0 model device. But, starting from the fifth conductor, the connectors begin to differ. The blue, fifth, wire conveys the information that has a negative value. The yellow conductor conveys positive information.

You can also pinout the device according to colors that are suitable for the connectors of all devices. The advantage of such connectors is that when using them no need to restart your computer or even try to somehow manually install all the necessary drivers.