Programmable logic devices with bidirect ional cascades
US6747480B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 12, 2002 |
| Grant date | Jun 8, 2004 |
| Priority date | — |
| Expiry date | Aug 26, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K19/17736
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A programmable logic integrated circuit device has a plurality of regions of programmable logic disposed on the device in a plurality of intersecting rows and columns of such regions. The regions of logic may include logic subregions that each have a look-up table. Interconnection resources (e.g., inter-region and intra-region interconnection conductors, signal buffers and drivers, programmable connectors, etc.) are provided on the device for making programmable interconnections between the look-up tables. Programmable bidirectional cascade circuitry that is distinct from the interconnections may be used to make connections directly from the output of one look-up table to another without using the interconnection resources. The programmable cascade circuitry may be programmed so that multiple look-up tables are interconnected to form sequential cascade chains or cascade trees.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.