USB Cheat Sheet

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Pangram verdict · v3.3

We believe that this document is fully human-written

1 %

AI likelihood · overall

Human

100% human-written 0% AI-generated

SEGMENTS · HUMAN 5 of 5

SEGMENTS · AI 0 of 5

WORD COUNT 559

PEAK AI % 2% · §5

Analyzed

Apr 25

backend: pangram/v3.3

Segments scanned

5 windows

avg 112 words each

Distribution

100 / 0%

human / AI fraction

Verdict

Human

Pangram v3.3

Article text · 559 words · 5 segments analyzed

Human AI-generated

§1 Human · 1%

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

§2 Human · 1%

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 Totala Encoding Effective bb Effective Bb Real Lifec USB 3.2 Gen 1x1 5,000 Mbps 5,000 Mbps 8b/10b 4,000 Mbps 500 MiB/s 400 MiB/s[1] USB 3.2 Gen 1x2 5,000 Mbps 10,000 Mbps 8b/10b 8,000 Mbps 1,000 MiB/s 800 MiB/s USB 3.2 Gen 2x1 10,000 Mbps 10,000 Mbps 128b/132b 9,696 Mbps 1,212 MiB/s 780 MiB/s[2] USB 3.2 Gen 2x2 10,000 Mbps 20,000 Mbps 128b/132b 19,392 Mbps 2,424 MiB/s

§3 Human · 1%

1,600 MiB/s[4] USB 4 Gen 2x2 10,000 Mbps 20,000 Mbps 128b/132b 19,392 Mbps 2,424 MiB/s 1,600 MiB/s USB 4 Gen 3x2 20,000 Mbps 40,000 Mbps 128b/132b 38,787 Mbps 4,848 MiB/s 2,700 MiB/s[5]

Note: Multi-lanes systems, uses lane striping (on TX) and lane bonding (on RX). a - What they put on the box. b - Rate with encoding overhead. e.g, 8b/10b = 20%. c - Real life sequencial read rate.

Cables 4 wires: PWR, GND, D+, D-. 8 wires: PWR, GND, D+, D-. RX+ , RX- , TX- , TX+. 12 wires: PWR, GND, D+, D-, RX1+, RX1-, RX2-, RX2+, TX1+, TX1-, TX2-, TX2+. Note: 1 USB lane = 1 twisted wire pair +/-. Note: 4 wires = 1 half-duplex lane, 8 wires = 2 lanes (one up, one down), and 12 wires = 4 lanes (two up, two down).

USB-A/B: Connectors 4/8 wires

Type-A 4-wires Type-A 8-wires Type-B 4-wires Type-B 8-wires

USB-C: Connectors 12 wires Only the USB Type-C connector has enough pins to support two lanes.

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- CC1 and CC2 are downstream facing port (DFP) and upstream facing port (UFP) detection. Also used for power negotiation and alt mode switch. - SBU1 and SBU2 are secondary bus wires, for the DisplayPort AUX channel and hot plug detection (HPD).

Charge rates / Cable types

Specifications Max. Voltage Max. Current Max. Power USB 2.0 5V 500mA 2.5W USB 3.0 / USB3.1 5V 900mA 4.5W USB Battery Charging (BC) 1.2 5V 1.5A 7.5W USB-C Current Mode (non-PD) 5V 3A 15W USB-C / Power Delivery (PD 1/2) 20V 5A 100W

USB-C PD 3.1 (EPR) 48V 5A 240W

Specifications USB 1.0 (Jan, 1996). USB 1.1 (Sep, 1998). USB 2.0 (Apr, 2000). USB 3.0 (Nov, 2008). USB 3.1 (Jul, 2013). USB 3.2 (Sep, 2017).

§5 Human · 2%

USB 4.0 (Aug, 2019).

References^ [1]Universal Serial Bus Revision 3.0 Specification^ [2]Real-world USB 3.2 Gen 2 Performance^ [3]USB 3.1 Tested: Performance^ [4]World’s First USB 3.2 Demonstration | Synopsys^ [5]USB4.0 M.2 NVMe Enclosure Review *