USB Connectors: Everything you Need to Know About Them


USBs are an essential part of the majority of electronic devices. Also, most of us use USB connectors to charge our portable devices.

USB stands for Universal Serial Bus. In the 1990s, scientists developed it to simplify the connection-making technique between computers and external devices. However, a pool of USB versions to choose from is often confusing. If you don’t get a complete insight into USB specifications, replacing it will be hard.

Here’s the complete guide on the properties and types to help you select USB connectors.

Table of Contents

USB Connectors and their properties

Here are some essential properties of USB connectors.


The standard connections are more resilient than previous connectors. Because USB is hot-swappable, You might use the links more often and carelessly.

Standard USB has minimal estimated durability of 1,500 mating insertion and removal cycles. In contrast, manufacturers have designed the mini-USB to have 5,000 bikes and the newer Micro-USB and USB-C receptacles to have 10,000 cycles. They added a locking device to improve durability and transferred the leaf spring from the jack to the plug. 

Nowadays, a plastic tongue protects the pins in a USB connection, and a metal casing typically covers the entire connecting mechanism. In addition, the shell of the plug contacts the receptacle before the pins. Grounding the surface dissipates static energy and shields the wires within the connection.


There are some tolerance levels that the USB standards define for each USB connector. That way, you can find the compatible connector available in the market and minimize physical disconnection. 

Moreover, some standards also specify the size of the connecting device around the plug.

Hence, every compliant device must support specific sizes or cables.


Each USB connector type has its pin layout. The USB 2.0 has two wires for data transmission (Vbus and Ground or GND) and two for differential serial data signals. Mini and Micro connectors have moved the GND connections from pin#4 to pin#5 so that pin 4 acts as an ID pin.

However, in USB 3.0, two additional differential pairs provide full-duplex data at Superspeed.


As you talk about colors, connectors are color-coded to differentiate between them. However, not every USB 3.0 needs to have the same color.

USB Connector Types

As the specifications for certain USBs have grown, there are a lot of connectors emerging in the market. Here are some common connector types that you will observe.

Different USB Connector interface, including USB Type-C Connectors

Caption: Different USB Connector interfaces, including USB Type-C Connectors

USB Type-A connector, Micro-B connector

USB Standard connectors

The type-A receptacle is a long rectangle with a rectangular cross-section. You can insert this plug into the type-A port of a USB host or hub, and it can carry both power and data. Moreover, USB devices, like keyboards and mice, have type-A plugs on the end of their cords.

The type-B socket has beveled edges on the top, thus making this plug have a nearly square cross-section. It connects to an upstream port on a device, such as a printer, through a detachable cable. Also, the type-B receptacle on specific devices lacks any data connections. It is purely intended to take power from the upstream device. Hence, it is impossible for a user to unintentionally create a loop with a two-connector design (A/B).

standard USB port

Caption: standard USB port

Mini connectors

To accommodate smaller devices like digital cameras, cellphones, and tablets, USB 2.0 in April 2000 introduced mini-USB ports. Since May 2007, the Mini-A and Mini-AB connectors have been discontinued.

The Mini-B USB connection was the standard for transmitting data to and from early cellphones and PDAs; however, it is not On-The-Go-compliant. The Mini-A and Mini-B plugs have a three by Seven mm and seven by three mm size, respectively (0.12 by 0.28 in).

Micro connectors

Micro connectors have a thickness, of half of the mini connectors. Thus you can integrate these into small portable devices. Additionally, using them in smaller devices was the main intention of inventing the micro connectors.

Micro plugs have a rating of 10000 disconnecting cycles, and you experience less mechanical wear and tear. Also, you can replace them quickly if they work no longer.

USB 3. X connectors and backward compatibility

USB 3.0 is backward compatible. They have SuperSpeed plugs and connectors like Micro Type B size. Moreover, extra pins in the latest design achieve a higher speed than the USB 1.0 version.

USB On-The-Go connectors

USB OTG connectors perform both the roles of an enslaver and an enslaved person. It means that they act as a host to one end and as a peripheral device to the other. Thus, it gives you an outer path to the connected devices that you might not attach directly.

USB-C Cable Connectors

USB type C came into existence in august 2014. These plugs connect both host and devices and replace type A and B connectors. As USB-C ports have the latest configuration, they have growing popularity. They can be found on every other device for data transmission and charging.

Speed Standards of Different Types of USB Connectors

Using USB with Laptop

Caption: Using USB with Laptop

USB connector types are not the only thing you will work on. Instead, the speed of transferring the data is also essential. 

There are five speeds for USB data transfer: Low Speed, Full Speed, High Speed, SuperSpeed, and SuperSpeed+. T USB connections aren’t like other types of data buses. Instead, some ports face downstream and provide power. Hence, most companies choose the topology to avoid overheating and damaged equipment.

Additionally, a single connector type is not associated with one standard. Thus you have to check out the standard USB speeds label separately on each cable.

  • USB 1.1: It was the standard speed of the USB and was available with legacy connectors. However, it is highly unlikely to find it on modern-day devices with advancements in technology.
  • USB 2.0: This speed standard opened gates to many modern-day USB norms, including mini and micro USB cables, OTG, and others. However, it is the slowest speed in this era and is often found in cheap flash drives, mice, keyboards, etc.
  • USB 3.0/3.1: The companies follow the USB 3. x as the current device standard. It provides you with much more data transfer speed and thus is the preferable standard these days. Moreover, you can identify the device using this standard by blue color in its port or SS symbol.
  • USB 4.0: Moving on from USB 3. x, now devices are opting for the USB 4.0 standard. However, it is not generally available as manufacturers adopt the new norms. Hopefully, you will see the 4.0 standard devices in the next few years.

Common Application of USB connectors

USB Types for Computer and Mobile Device

Caption: USB Types for Computer and Mobile Device

The different real-life examples of USB connector types are as below.

USB A-Type

A-Type USB connectors are a flat rectangular interface. It holds the connection firmly, thus making it easier for the user to connect and disconnect. Usually, USB A-type connects peripherals devices with computers.

USB B-Type

For usage with USB peripherals, the B-style connection has been devised. Like the A connection, it relies on the body of the connector to hold it in place. The B-socket, an “upstream” connector is only seen on peripheral devices like mice and keyboards. As a result, an A-B cable occurs for most USB applications.

USB C-Type

USB Type-C Connectors have a reversible or symmetrical design so that you don’t need to worry about their orientation. Also, it is capable of supporting USB 3.1, 3.0 2.0, and 1.1 signals. It is paired with a USB type A, B, or micro version to make it compatible with older devices.

Micro-USB B

The Micro-USB B connection is more minor in size than a USB Mini-b. However, it still supports the 480 Mbps transfer rate and On-The-Go functionality. The tiny 5-pin connector has a black receptacle, making it easy to spot. Modern mobile gadgets use this connection, such as smartphones, GPS units, PDAs, and digital cameras.

USB Mini-b (5-pin)

The Mini-B 5-pin is a variation of USB Type-B. Since the USB B type was significant, it could not support many electronic devices, such as digital cameras, PDAs, etc. Thus, the USB Mini-B connector is the popular style many peripheral devices used for data communication.

USB Mini-b (4-pin)

It is just like standard B-type USB connectors but is much smaller. In some cases, the manufacturers use mini-b 4-Pin connectors. For example, Kodak uses 4-Pin Mini B connectors in its digital cameras.

USB 3.0 A-Type

The USB 3.0 A-style connection is a flat, rectangular interface often seen on host controllers in computers and hubs. The A-socket connector is designed for usage on host controllers and hubs only. Also, the A-Type connection used in USB 2.0 and USB 1.1 applications is comparable in size and form. The USB 3.0 A-type features extra pins not seen in the USB 2.0 or 1.1 A-type.

USB 3.0 B-Type

USB 3.0 devices have a B-Type connection. Moreover, this connection carries data and power through USB SuperSpeed. But, this connector is not backward compatible with USB 2.0 or 1.1 devices, although USB 3.0 devices can take older USB 2.0 and 1.1 cables.

USB 3.0 Micro B

USB 3.0 devices use the Micro B connection. This connection carries data and power through USB SuperSpeed. However, it is not compatible with USB 2.0 or 1.1 devices.

Micro-USB AB

Exclusively for USB On-The-Go devices, this adapter accepts Micro-USB A or Micro-USB B cables. This connection type is only seen on On-The-Go gadgets and does not appear on wires. The grey receptacle and small five-pin design distinguish this interface.

Micro-USB A

Micro-USB A is physically smaller than USB Mini-b but supports 480 Mbps transfer rates and On-The-Go functionality. The bright receptacle and compact five-pin shape help identify the connection.

USB Mini-b (Fuji®)

It is an unauthorized connection found on many digital cameras, notably Fuji® models. Its flat, rectangular form recalls an A-style relationship.


There are so many types of USB cables based on the USB type. You should pick a suitable cable for charging and transferring data from your mobile device. Here at Bloom, we manufacture USB cable to match different types of USB ports on your USB device.