Identifying content-addressable memory entries differing from a lookup word in multiple but less than a predetermined number of bit positions
US7266004B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 18, 2005 |
| Grant date | Sep 4, 2007 |
| Priority date | — |
| Expiry date | Nov 8, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C15/04
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A content-addressable memory entry is identified as being matched if it matches all bit positions of a lookup word or does not match for less than a predetermined number of bit positions. A match line of the content-addressable memory entry is precharged. During a subsequent matching phase, each of the bit positions of the content-addressable memory entry provides a discharge path for the precharged match line. Whether or not the content-addressable memory should be identified as being matched is then determined typically by comparing the match reference voltage of the match line to a predetermined voltage level at a predetermined time, with the predetermined voltage level and predetermined time selected for the allowed number of bit positions that do not have to be matched while still considering the content-addressable memory entry to have been matched, and the implementation technology of the embodiment.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.