Programmable logic device
US6255847A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 21, 1998 |
| Grant date | Jul 3, 2001 |
| Priority date | — |
| Expiry date | May 21, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K17/163
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An improved programmable logic device includes a set of I/O cells, a set of logic blocks, and a routing pool that provides connections among the logic blocks and the I/O cells. At least one of the logic blocks includes a programmable logic array that generates product term output signals on product term output lines. A first product term summing circuit has input terminals, at least one of which is coupled to a product term output line. The first product term summing circuit generates an output signal at an output terminal in response to at least one product term output signal. Likewise, a second product term summing circuit has input terminals, at least one of which is coupled to a product term output line. The second product term summing circuit generates an output signal at an output terminal in response to at least one product term output signal. The logic block further includes first and second output lines and a first programmable switching device that programmably couples the first output line to the output terminal of either the first or the second product term summing circuit. The logic block further includes a second programmable switching device that programmably couples…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.