Methods and apparatus for electrically terminating a high speed communications pathway
US5473264A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 13, 1992 |
| Grant date | Dec 5, 1995 |
| Priority date | — |
| Expiry date | Nov 13, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L25/0298
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A circuit arrangement and methods for sensing whether line terminator devices are present at terminal ends of high speed communications pathways, and enabling a switching terminator in accordance therewith, are disclosed. In one embodiment, the communications pathway comprises a Small Computer System Interface (SCSI) bus comprising internal and external bus segments and bus control lines, including a reset line consisting of internal and external reset line segments. First and second system reset signals are supplied from a central processor unit (CPU) to various system components. Line terminator devices may or may not be coupled to the ends of the internal and external bus segments. The first system reset signal is directed to first and second transistors coupled together in an "upside down" collector-to-emitter configuration comprising a two-quadrant bidirectional switch which opens upon assertion of the first system reset signal. The internal and external reset request lines are coLtpied to the collectors of the first and second transistors respectively, and further form inputs to a NAND gate. First and second resistors having impedances large relative to the impedance of line …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.