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. 19, 1990
Filed:
Jun. 24, 1988
Hideshi Miyatake, Kyogo, JP;
Hiroyuki Yamasaki, Kyogo, JP;
Masaki Shimoda, Kyogo, JP;
Kazuhiro Tsukamoto, Kyogo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A word line driving signal generating circuit and a sense amplifier activating signal generating circuit are provided for every partitioned memory cell array. When the levels of an external RAS signal and an external CAS signal have a predetermined relation and an external RNC signal remains at a predetermined potential or more, a refresh operation is started. A refresh address is generated from a refresh address counter in a sense restore control circuit. All of the memory cell arrays are simultaneously refreshed in response to the address. On this occasion, an operation for selecting a column by a column decoder provided in each of the memory cell arrays is inhibited. In the case in which an input of the external RNC signal is not prepared, when the levels of the external RAS signal and the external CAS signal have a predetermined relation and this state is held in a predetermined time period or more, the same refresh operation as described above is started.