Low-power USB superspeed device with 8-bit payload and 9-bit frame NRZI encoding for replacing 8/10-bit encoding
US8166221B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 6, 2010 |
| Grant date | Apr 24, 2012 |
| Priority date | — |
| Expiry date | Nov 2, 2030 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02D10/00
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A Low-power flash-memory device uses a modified Universal-Serial-Bus (USB) 3.0 Protocol to reduce power consumption. The bit clock is slowed to reduce power and the need for pre-emphasis when USB cable lengths are short in applications. Data efficiency is improved by eliminating the 8/10-bit encoder and instead encoding sync and framing bytes as 9-bit symbols. Data bytes are expanded by bit stuffing only when a series of six ones occurs in the data. Header and payload data is transmitted as nearly 8-bits per data byte while framing is 9-bits per symbol, much less than the standard 10 bits per byte. Low-power link layers, physical layers, and scaled-down protocol layers are used. A card reader converter hub allows USB hosts to access low-power USB devices. Only one flash device is accessed, reducing power compared with standard USB broadcasting to multiple devices.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.