The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 11, 2002
Filed:
Jun. 07, 1995
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A semiconductor memory device comprises a DRAM memory cell array comprising a plurality of dynamic type memory cells arranged in a plurality of rows and columns, and an SRAM memory cell array comprising static type memory cells arranged in a plurality of rows and columns. The DRAM memory cell array is divided into a plurality of blocks each comprising a plurality of columns. The SRAM memory cell array is divided into a plurality of blocks each comprising a plurality of columns, corresponding to the plurality of blocks in the DRAM memory cell array. The SRAM memory cell array is used as a cache memory. At the time of cache hit, data is accessed to the SRAM memory cell array. At the time of cache miss, data is accessed to the DRAM memory cell array. On this occasion, data corresponding to one row in each of the blocks in the DRAM memory cell array is transferred to one row in the corresponding block in the SRAM memory cell array.