Universal Serial Bus

Overview

The Universal Serial Bus (USB) is an industry-standard interface for connecting peripherals to computers and electronic devices. First introduced in 1996, it has become the dominant connectivity standard for data transfer and power delivery, replacing legacy interfaces like serial/parallel ports and PS/2 connectors.

USB continues to evolve as a universal interface, with USB-C now adopted in 98% of new consumer electronics and projected to remain dominant through the 2030s.

Key Specifications

Versions and Speeds:

USB 1.x (1996): Low Speed (1.5 Mbps) Full Speed (12 Mbps)

USB 2.0 (2000): High Speed (480 Mbps)

USB 3.x (2008–2017): SuperSpeed (5 Gbps)

USB 3.2 Gen 1 SuperSpeed+ (10–20 Gbps)

USB 3.2 Gen 2/2x2

USB4 (2019): Up to 40 Gbps (based on Thunderbolt™ 3 protocol)

Power Delivery

standard 5V/0.5A (USB 2.0)

USB Power Delivery (PD):

Up to 240W (USB PD 3.1, 2021)

Supports variable voltage (5–48V)

Connector Types

Core Features

Plug-and-Play: Automatic device recognition Hot-Swapping: Devices can be connected/disconnected without rebooting Backward Compatibility: Supports older USB versions Dual Roles: Devices can act as hosts (USB On-The-Go)

Applications

Data Transfer: External drives, smartphones Peripheral Connectivity: Keyboards, mice, printers Power Delivery: Laptop charging, fast smartphone charging Audio/Video: USB-C Alt Mode for DisplayPort/HDMI

Current Standards

USB4 v2.0: 80 Gbps bidirectional bandwidth (released 2023) USB PD 3.2: Enhanced safety protocols for high-power devices Wireless USB: Emerging standard for short-range wireless data/power

Governance

Managed by the USB Implementers Forum (USB-IF), which oversees certification programs to ensure interoperability across 50,000+ certified devices.

USB Videos