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:
Nov. 19, 1996
Filed:
May. 11, 1995
Yoshinori Kasuta, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
An object of the present invention is to provide a semiconductor memory device having a function to efficiently limit a voltage amplitude of an I/O line pair 4 to protect cell data from destruction even when multiple selection, etc., occurs at a column gate 3. A semiconductor memory device 1 constituted by DRAM, etc., for transferring cell data amplified by a sense amplifier 2 to an I/O line pair 4 through a transfer gate 3, comprises an amplitude limiting means 5 for limiting the amplitude of a voltage, provided to the I/O line pair 4 in activation, wherein the amplitude limiting means 5 includes a first amplitude limiting circuit 51 having a predetermined operating range and a second amplitude limiting circuit 52 having an operating range different from the operating range of the first amplitude limiting circuit 51.