Clock skew reduction using spider clock trace routing
US5861764A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 31, 1996 |
| Grant date | Jan 19, 1999 |
| Priority date | — |
| Expiry date | Dec 31, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2201/09254
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A technique for reducing skew between clock signals in a digital system requiring multiple clock signals. The system preferably is implemented on a printed circuit board. An oscillator circuit provides a periodic signal to a clock buffer which generates multiple periodic clock signals. The clock signals are provided to various destination points on the printed circuit board. The rising and falling edges of each clock signal generated by the clock buffer do not occur precisely at the same time as the rising and falling edges of the other clock signals. This misalignment of clock edges, or skew, is detrimental to system performance, but is reduced substantially by connecting all of the clock buffer's output clock signals together at a single physical point or node. Accordingly, the printed circuit board traces carrying each of the clock signals are routed to a single point node. A single point node is used to reduce skew caused by the clock buffer. Single point nodes also may be used at various locations on the printed circuit board to reduce skew caused by differences in the lengths of the traces carrying the clock signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.