Multiplexing a ground signal on a high speed cable interface to provide access to cable vital product data
US7624203B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 4, 2006 |
| Grant date | Nov 24, 2009 |
| Priority date | — |
| Expiry date | Nov 7, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F13/4081
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Because cable length affects signal quality, amplifying signals differently to account for cable length (“tuning”) becomes especially important when high speed signals are used. Cable length information may be stored in a non-volatile memory which may be integrated into a cable assembly or may be a discrete component between the cable and an interface. Rather than using a dedicated data line to the memory component a ground line may be connected to the memory component and multiplexed. During normal operation the selected line is grounded through a switching device. When a cable is detected, a management controller changes the state of the switching device to decouple the selected line from ground to allow the management controller access to the data stored in the memory component, including cable length information. The selected line is then re-coupled to ground and interface circuits may be tuned for the cable length.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.