Stored don't-care based hierarchical search-line scheme
US7525827B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 15, 2007 |
| Grant date | Apr 28, 2009 |
| Priority date | — |
| Expiry date | Mar 3, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C15/04
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
In the proposed stored don't-care hierarchical search-line scheme, a content-addressable memory (CAM) is divided into several blocks. Each block contains a plurality of local search-lines, a global search-line, a buffer and a memory memory cell. Data are stored in the blocks in order according to the length of the prefix. Data with the longest prefix is stored at the bottommost, and its don't-care state is used as the control signal of the buffer to control whether to transfer the data on the global search-line to the local search-line or not. The local search-line then transfer the value into the memory cell. There is no complex control circuit and extra storage device needed. Moreover, because the control signal directly comes from the don't-care state, power consumption on search-lines can be effectively reduced with no increase of search delay.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.