The connectors the USB committee specifies support a number of USB's underlying goals, and reflect lessons learned from the many connectors the computer industry has used. The connector mounted on the host or device is called the receptacle, and the connector attached to the cable is called the plug. [1] The official USB specification documents also periodically define the term male to represent the plug, and female to represent the receptacle, though these uses are inconsistent with established definitions of connector gender. [2]

The USB-C connector supersedes all earlier USB connectors and the Mini DisplayPort connector. It is used for all USB protocols and for Thunderbolt (3 and later), DisplayPort (1.2 and later), and others. Developed at roughly the same time as the USB3.1 specification, but distinct from it, the USB-C Specification 1.0 was finalized in August 2014 [24] and defines a new small reversible-plug connector for USB devices. [25] The USB-C plug connects to both hosts and devices, replacing various Type-A and Type-B connectors and cables with a standard meant to be future-proof. [24] [26] Unlike other data buses (such as Ethernet), USB connections are directed; a host device has "downstream" facing ports that connect to the "upstream" facing ports of devices. Only downstream facing ports provide power; this topology was chosen to easily prevent electrical overloads and damaged equipment. Thus, USB cables have different ends: A and B, with different physical connectors for each. Each format has a plug and receptacle defined for each of the A and B ends. A USB cable, by definition, has a plug on each end—one A (or C) and one B (or C)—and the corresponding receptacle is usually on a computer or electronic device. The mini and micro formats may connect to an AB receptacle, which accepts either an A or a B plug, that plug determining the behavior of the receptacle.

In May 2021, the USB PD promoter group launched revision 3.1 of the specification. [58] Revision 3.1 adds Extended Power Range (EPR) mode which allows higher voltages of 28, 36, and 48 V, providing up to 240 W of power (48 V at 5 A), and the "Adjustable Voltage Supply" (AVS) protocol which allows specifying the voltage from a range of 15 to 48 V in 100 mV steps. [71] [72] Higher voltages require electronically marked EPR cables that support 5 A operation and incorporate mechanical improvements required by the USB Type-C standard rev. 2.1; existing power modes are retroactively renamed Standard Power Range (SPR). In October 2021 Apple introduced a 140 W (28 V 5 A) GaN USB PD charger with new Macbooks. [73] USB2.0 provides for a maximum cable length of 5 meters (16ft 5in) for devices running at high speed (480Mbit/s). The primary reason for this limit is the maximum allowed round-trip delay of about 1.5μs. If USB host commands are unanswered by the USB device within the allowed time, the host considers the command lost. When adding USB device response time, delays from the maximum number of hubs added to the delays from connecting cables, the maximum acceptable delay per cable amounts to 26ns. [37] The USB2.0 specification requires that cable delay be less than 5.2ns/m ( 1.6ns/ft, 192 000 km/s), which is close to the maximum achievable transmission speed for standard copper wire.

Portable devices having a USB On-The-Go port may want to charge and access a USB peripheral simultaneously, yet having only a single port (both due to On-The-Go and space requirement) prevents this. Accessory charging adapters (ACA) are devices that provide portable charging power to an On-The-Go connection between host and peripheral. Before the Battery Charging Specification was defined, there was no standardized way for the portable device to inquire how much current was available. For example, Apple's iPod and iPhone chargers indicate the available current by voltages on the D− and D+ lines. When D+ = D− = 2.0V, the device may pull up to 900mA. When D+ = 2.0V and D− = 2.8V, the device may pull up to 1A of current. [53] When D+ = 2.8V and D− = 2.0V, the device may pull up to 2A of current. [54] Accessory charging adapters (ACA) [ edit ] The Type-A plug. This plug has an elongated rectangular cross-section, inserts into a Type-A receptacle on a downstream port on a USB host or hub, and carries both power and data. Captive cables on USB devices, such as keyboards or mice, terminate with a Type-A plug. USB-C can do more than other USB types can, and get it done faster. USB-C has the potential to replace all other cables, thanks to its diverse multi-tasking abilities. It has the ability to power even the most power-hungry devices, like laptops and TVs. It can also transfer 40 gigabits of data per second (Gbps), and can be used to deliver 5K video to external monitors.

Micro B Usb Cables

It is also reversible, i.e., it can be plugged in either way without worrying about which is the right side up. Some non-standard USB devices use the 5V power supply without participating in a proper USB network, which negotiates power draw with the host interface. Examples include USB-powered keyboard lights, fans, mug coolers and heaters, battery chargers, miniature vacuum cleaners, and even miniature lava lamps. In most cases, these items contain no digital circuitry, and thus are not standard-compliant USB devices. This may cause problems with some computers, such as drawing too much current and damaging circuitry. Prior to the USB Battery Charging Specification, the USB specification required that devices connect in a low-power mode (100mA maximum) and communicate their current requirements to the host, which then permits the device to switch into high-power mode. USB Type-C: USB Type-C is a newer and versatile connector that is becoming increasingly popular. It is reversible like Micro-USB but has a smaller form factor. USB Type-C cables can be used for charging devices, data transfer, and connecting various peripherals. They support faster data transfer speeds and can deliver more power.

Battery Charging v1.2 Spec and Adopters Agreement" (PDF (Zipped)). USB.org. March 15, 2015. Table 5-1 Voltages. Archived (PDF (Zipped)) from the original on November 3, 2021 . Retrieved November 3, 2021. Cai Yan (31 May 2007). "China to enforce universal cell phone charger". EE Times. Archived from the original on 29 September 2007 . Retrieved 25 August 2007. On-The-Go and Embedded Host Supplement to the USB Revision 3.0 Specification" (PDF). USB.org. Revision 1.1. May 10, 2012.

Howse, Brett. "USB Type-C Connector Specifications Finalized". AnandTech. Archived from the original on March 18, 2017 . Retrieved April 24, 2017. a b c "Universal Serial Bus Micro-USB Cables and Connectors Specification" (PDF). USB Implementers Forum. April 4, 2007. Archived (PDF) from the original on November 15, 2015 . Retrieved January 31, 2015.

The Micro plug design is rated for at least 10,000 connect-disconnect cycles, which is more than the Mini plug design. [13] [16] The Micro connector is also designed to reduce the mechanical wear on the device; instead, the easier-to-replace cable is designed to bear the mechanical wear of connection and disconnection. The Universal Serial Bus Micro-USB Cables and Connectors Specification details the mechanical characteristics of Micro-A plugs, Micro-AB receptacles (which accept both Micro-A and Micro-B plugs), Double-Sided Micro USB, and Micro-B plugs and receptacles, [16] along with a Standard-A receptacle to a Micro-A plug adapter. As you can imagine, the design of the lightning connector makes it impossible to be used in any other device other than Apple devices, which makes it a nuisance for many users. So, if you are transferring data from your phone to your laptop via a USB cable, you will plug your phone (host) into the laptop’s USB port (receptor). USB Mini are further divided into two variants: USB Mini A (or Mini USB A) and USB Mini B. These are smaller counterparts of Type A and Type B USB connectors. They are designed for their compact size, which makes them handy for smaller devices. USB Mini A and USB Mini B connectors. (Photo Credit: Wikimedia Commons)Programming and Debugging: USB cables are essential for programming and debugging certain electronic devices.