Comparison circuit utilizing a differential amplifier
US5973955A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 2, 1998 |
| Grant date | Oct 26, 1999 |
| Priority date | — |
| Expiry date | Feb 2, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C15/04
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A pipelined dual port integrated circuit memory (20) includes an array (30) of static random access memory (SRAM) cells. A control circuit (32) controls access to the memory cells, where substantially simultaneous requests for access are serviced sequentially within a single cycle of a clock signal of a data processor that is accessing the memory (20). An address collision detector (110) uses both a differential amplifier (360) included within a D-flip-flop circuit (114) and a reference voltage provided by a reference voltage circuit (365) to compare addresses provided to the two ports, and generates a match signal that is used for determining which of the two ports are serviced first, independent of which port is read from, or written to. Because dual port functionality is obtained using a single port SRAM array (30), the memory (20) may be manufactured using relatively less integrated circuit surface area, and therefore at a lower cost.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.