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. 15, 2009
Filed:
Aug. 22, 2007
Hiroyoshi Tomita, Kawasaki, JP;
Hiroyoshi Tomita, Kawasaki, JP;
Fujitsu Microelectronics Limited, Tokyo, JP;
Abstract
The present invention detects a sense amplifier having an unbalanced characteristic. In a test method for a semiconductor memory device for detecting a sense amplifier having an unbalanced characteristic, an intermediate potential having different H and L levels from normal operation is restored in a first memory cell of a first bit line connected to a test target sense amplifier, charge quantity when the capacitance of the capacitor is small is virtually stored in the first memory cell, then the data of the first memory cell is read, and a malfunction of the sense amplifier is checked based on the presence of an error of read data.