Topics / Networks and Data Transmission / Universal Serial Bus (USB)
Universal Serial Bus (USB)
Universal Serial Bus (USB) is a type of cable and connector commonly used for half-duplex or full-duplex serial data transmission between a computer and attached devices.
A USB cable consists of a shielded casing containing four wires. Two wires are used for power and earth, and the other two wires are used for data transmission.
Typical cables can reach up to 5 metres.
There are many benefits to using USB cables:
- USB is widely used and available on most computers and connected devices. When buying a new device, we just assume that it will connect via USB, safely knowing that our computer will have the appropriate ports to make that connection
- Devices connected by USB are automatically detected by the computer (and device drivers loaded if available)
- USB cables can’t be connected incorrectly (unless you apply some serious force!)
- Various different transmission speeds are supported, ranging from the slow and dated USB 1.0 (1.5 Mbps) through to the very fast present day USB 4 (40 Gbps)
- No need for an external power supply for your small device. USB cables carry power and data
- Hubs allow additional ports to be created
- USB is backward compatible. However you will only benefit from the faster speeds if both devices support it
USB-C connectors are growing in adoption. These are beneficial because:
- They provide USB data transmission, but usually at the higher rates (10 Gbps+)
- Can be connected both ways up (there is no correct orientation)
- USB-C can carry much more power, allowing larger devices to be powered without external power sources
- They are generally more robust
