Detecting connection to a USB host or hub without using an extra status input
US7644217B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 2, 2007 |
| Grant date | Jan 5, 2010 |
| Priority date | — |
| Expiry date | Aug 25, 2027 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02D30/50
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A low power Universal Serial Bus (USB) capable device uses a weak pull-up resistance that is coupled to at least one data line of the USB for detection of when the USB capable device is connected to a USB host or hub. When the USB capable device is not connected to the USB host or hub, USB peripheral, including the USB transceiver, USB voltage regulator, serial interface and/or USB logic circuits required for USB operation may be powered down to conserve power drawn by the USB capable device. When the USB capable device is connected to the USB host or hub, a voltage from the weak pull-up will be significantly reduced, thus signaling that the USB peripheral and associated circuits should be powered up for normal USB operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.