Redundant, synchronous central timing systems with constant master voltage controls and variable slave voltage controls
US6658580B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 11, 2000 |
| Grant date | Dec 2, 2003 |
| Priority date | — |
| Expiry date | Mar 3, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K1/14
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
The present invention provides a network device including redundant, synchronous central timing subsystems (CTSs) each having a voltage controlled timing circuit for receiving a constant master voltage signal and variable slave voltage signal. Each CTS also includes a control logic circuit for selecting the constant master voltage signal for use by the voltage controlled timing circuit when the CTS is master and for selecting the variable slave voltage signal when the CTS is slave. Using a constant master voltage signal eliminates the need for a separate master oscillator in each CTS. Oscillators are typically expensive, consume significant space on the printed circuit board and have location restrictions on where they may be placed on the printed circuit board.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.