Adaptive bus termination apparatus and methods
US9214939B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 10, 2014 |
| Grant date | Dec 15, 2015 |
| Priority date | — |
| Expiry date | Jul 10, 2034 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02D10/00
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Termination impedance of a digital signal bus is adaptively selected as a function of a present or anticipated state of the bus. A variable termination resistor is arranged in series between a termination switch and a common voltage node at the termination end of each bus conductor. Information regarding the current or anticipated bus state is received from an external device such as a bus controller or may be derived by sensing activity on the bus. For example, clock frequency detection logic coupled to clock lines of the bus senses the current operational speed of the bus. A highest-value termination resistance predetermined to be consistent with reliable bus operation under conditions of the current or anticipated bus state is selected for each bus conductor. A bus conductor termination may be taken to a high impedance state by opening the associated termination switch. Decreased average bus power consumption may result.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.