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:
Dec. 30, 1997
Filed:
Mar. 04, 1997
Tokuya Osawa, Tokyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
It is an object to provide a test circuit which properly finds faults of memory cells of a storage circuit. Registers XB1, 0, YB1, 0 of a circuit SGC1 supply address data which includes four order all cycle sequence. A generating portion 10a provides '1' when data XB1, 0 are '10' and provides '0' in other cases. A generating portion 11a provides '1' when data XB1,0 are '01' and provides '0' in other cases. One of the outputs of the generating portions 10a, 11a is selected with the data YB1 and a selector S and provided to a RAM 1 as data DI. In the RAM 1, one of word lines is selected by X address data and data of memory cells MC are applied onto bit lines bit 0-3. With this structure, the logic on the bit line selected by the Y address data changes from '0' to '1' or from '1' to '0'.