USB Connectors explained

You looking for the right USB connector, here are the different styles of connectors that are Industry Standard.



Information Below is sourced from


Connector TYPES


USB 1.x/2.0 standard pinout
Pin Name Cable color Description
1 VBUS Red +5 V
2 D− White Data −
3 D+ Green Data +
4 GND Black Ground
Micro-B USB 3.0 compatible socket
USB 2.0 connector on the side of the specification standard micro USB 3.0 connector are aligned pin-minute increase in the standard.
No.1: power (VBUS)
No.2: USB 2.0 differential pair (D−)
No.3: USB 2.0 differential pair (D+)
No.4: USB OTG ID for identifying lines
No.5: GND
No.6: USB 3.0 signal transmission line (−)
No.7: USB 3.0 signal transmission line (+)
No.8: GND
No.9: USB 3.0 signal receiving line (−)
No.10: USB 3.0 signal receiving line (+)

USB 1.x/2.0 Mini/Micro pinout

Pin Name Cable color Description
1 VBUS Red +5 V
2 D− White Data −
3 D+ Green Data +
4 ID None Permits distinction of A plug from B plug
* A plug: connected to Signal ground
* B plug: not connected
5 GND Black Signal ground



There are several types of USB connectors, including some that have been added while the specification progressed. The original USB specification detailed Standard-A and Standard-B plugs and receptacles. The first engineering change notice to the USB 2.0 specification added Mini-B plugs and receptacles.

The data connectors in the Standard-A plug are actually recessed in the plug as compared to the outside power connectors. This permits the power to connect first which prevents data errors by allowing the device to power up first and then transfer the data. Some devices will operate in different modes depending on whether the data connection is made. This difference in connection can be exploited by inserting the connector only partially. For example, some battery-powered MP3 players switch into file transfer mode and cannot play MP3 files while a USB plug is fully inserted, but can be operated in MP3 playback mode using USB power by inserting the plug only part way so that the power slots make contact while the data slots do not. This enables those devices to be operated in MP3 playback mode while getting power from the cable.

To reliably enable a charge-only feature, modern USB accessory peripherals now include charging cables that provide power connections to the host port but no data connections, and both home and vehicle charging docks are available that supply power from a converter device and do not include a host device and data pins, allowing any capable USB device to be charged and/or operated from a standard USB cable.


 USB standard connectors

Pin configuration of the USB connectors Standard A/B, viewed looking into face/end of plug

The USB 2.0 Standard-A type of USB plug is a flattened rectangle which inserts into a "downstream-port" receptacle on the USB host, or a hub, and carries both power and data. This plug is frequently seen on cables that are permanently attached to a device, such as one connecting a keyboard or mouse to the computer via usb connection.

USB connections eventually wear out as the connection loosens through repeated plugging and unplugging. The lifetime of a USB-A male connector is approximately 1,500 connect/disconnect cycles.  

A Standard-B plug—which has a square shape with bevelled exterior corners—typically plugs into an "upstream receptacle" on a device that uses a removable cable, e.g. a printer. A Type B plug delivers power in addition to carrying data. On some devices, the Type B receptacle has no data connections, being used solely for accepting power from the upstream device. This two-connector-type scheme (A/B) prevents a user from accidentally creating an electrical loop.  


 Mini and Micro connectors

Various connectors have been used for smaller devices such as PDAs, mobile phones or digital cameras. These include the now-deprecated  (but standardized) Mini-A and the currently standard Mini-B, Micro-A, and Micro-B connectors.

The Mini-A and Mini-B plugs are approximately 3 by 7 mm. The micro-USB plugs have a similar width but approximately half the thickness, enabling their integration into thinner portable devices. The mini-A connector is 6.85 by 1.8 mm with a maximum overmold size of 11.7 by 8.5 mm. The mini-B connector is 6.85 by 1.8 mm with a maximum overmold size of 10.6 by 8.5 mm.

The Micro-USB connector was announced by the USB-IF on 4 January 2007. The Mini-A connector and the Mini-AB receptacle connector were deprecated on 23 May 2007. As of February 2009, many currently available devices and cables still use Mini plugs, but the newer Micro connectors are being widely adopted and as of December 2010, the Micro connectors are the most widely used. The thinner micro connectors are intended to replace the Mini plugs in new devices including smartphones and personal digital assistants. The Micro plug design is rated for at least 10,000 connect-disconnect cycles which is significantly more than the Mini plug design. The Universal Serial Bus Micro-USB Cables and Connectors Specification details the mechanical characteristics of Micro-A plugs, Micro-AB receptacles, and Micro-B plugs and receptacles, along with a Standard-A receptacle to Micro-A plug adapter.

The cellular phone carrier group, Open Mobile Terminal Platform (OMTP) in 2007 have endorsed Micro-USB as the standard connector for data and power on mobile devices. These include various types of battery chargers, allowing Micro-USB to be the single external cable link needed by some devices.

As of 30 January 2009 Micro-USB has been accepted and is being used by almost all cell phone manufacturers as the standard charging port (including HTC, Motorola, Nokia, LG, Hewlett-Packard, Samsung, Sony Ericsson, Research In Motion). 



Host interface receptacles

The following receptacles accept the following plugs:

Receptacle Plug
USB Std A.png USB Std B.png USB Mini B.png USB Micro A.png USB Micro B.png
USB Std A.png Yes No No No No
USB Std B.png No Yes No No No
USB Mini-B receptacle.png No No Yes No No
USB Micro-AB receptacle.jpg No No No Yes Yes
USB Micro-B receptacle.jpg No No No No