Patent · US Expired

Dynamic memory system which includes apparatus for performing refresh operations in parallel with normal memory operations

US4185323A · kind A · utility

25Cited by
3References
38Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 20, 1978
Grant dateJan 22, 1980
Priority date
Expiry dateJul 20, 1998

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C11/406
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A memory subsystem for processing memory requests includes at least a pair of independently addressable dynamic memory module units. Each memory unit includes arrays of memory elements corresponding to a number of storage locations, separate addressing and data output circuits. The system further includes common timing, refresh and control circuits. When the memory request specifies a predetermined type of memory operation, the control circuits generate signals for refreshing a location within the memory unit from which data is not being fetched. The control circuits, upon the completion of the refresh operation, in response to another predetermined memory request, refreshes the corresponding row within the other unit in parallel with fetching data from first unit. Upon completing refresh operations within both units, the control circuits generate a control signal for inhibiting the refresh circuits from performing a mandatory refresh operation, upon a row of memory elements within the memory units in which access to the memory system is inhibited temporarily, enabling memory operations to continue without interruption.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.