May 05, 2022

USB Cheat Sheet

I spend time investigating a non-existing bug today because I misunderstood a USB term. So I made myself a cheat sheet. Maybe it will save time to someone.

Marketing Name Also Known As Signal Gbps Signal MiB/s Wires Cable

USB 1.1 Full Speed 12 Mbps 1.5 MiB/s 4 4m

USB 2.0 Hi-Speed 480 Mbps 60 MiB/s 4 4m

SuperSpeed USB 5Gbps USB 3.0

USB 3.1

USB 3.2

USB 3.1 Gen 1

USB 3.2 Gen 1

5000 Mbps 625 MiB/s 8 3m

SuperSpeedPlus USB 10Gbps USB 3.1

USB 3.2

USB 3.1 Gen 2

USB 3.2 Gen 2

10000 Mbps 1250 MiB/s 8 2m

SuperSpeedPlus USB 20Gbps USB 3.2

USB 3.2 Gen 2x2

20000 Mbps 2500 MiB/s 12 1m

USB4 20Gbps USB4 Gen 2×2

USB4

20000 Mbps 2500 MiB/s 12 0.8m

USB4 40Gbps USB4 Gen 3×2

USB4

40000 Mbps 5000 MiB/s 12 0.8m

Gen naming Convention, lanes, and Speed

USB Gen A x B

A = Generation

B = Num lanes used

Name Signal Sig Total a Encoding Effective b b Effective B b Real Life c

USB 3.2 Gen 1 x 1 5,000 Mbps 5,000 Mbps 8b/10b 4,000 Mbps 500 MiB/s 400 MiB/s [1]

USB 3.2 Gen 1 x 2…