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:
Feb. 14, 2006
Filed:
May. 18, 2004
Applicants:
Tomonori Fujimoto, Osaka, JP;
Kiyoto Ohta, Osaka, JP;
Hirohito Kikukawa, Osaka, JP;
Inventors:
Assignee:
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11C 7/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
A row control circuit of a semiconductor memory device includes an oscillator as a clock oscillator for generating an internal clock, a D flipflop as a refresh request signal RFRQ generation circuit for generating a refresh request signal RFRQ synchronously with the internal clock, and a delay circuit, a NAND gate, an AND gate, a D flipflop, a delay circuit, an AND gate and an OR gate as refresh circuits. By using a refresh request signal RFRQ and an active signal ACT, internal refresh is performed internally in a DRAM separately from an external refresh command.