High density programmable logic device
US5869981A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 6, 1995 |
| Grant date | Feb 9, 1999 |
| Priority date | — |
| Expiry date | Jun 6, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K19/17744
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Each programmable logic device in at least two families of high density segmented programmable array logic device utilizes a programmable switch interconnection matrix to couple an array of symmetric programmable logic blocks. Each programmable logic block includes programmable logic macrocells, programmable input/output macrocells, a logic allocator and a programmable product term array. The programmable switch matrix provides centralized global routing with a fixed path independent delay and decouples the logic macrocells from the product term array. The logic allocator decouples the product term array from the logic macrocells, and the I/O macrocells decouple the logic macrocells from the package I/O pins. The logic allocator steers product terms from the product term array to selected logic macrocells so that no product terms are permanently allocated to a specific logic macrocell. In a first PLD of each family, a first predetermined number of input lines couple the switch matrix to each programmable logic block. In a second PLD of each family, a second predetermined number of input lines couple the switch matrix to each programmable logic block. The number of input lines to ea…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.