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. 08, 1988
Filed:
Jul. 09, 1986
Applicant:
Inventor:
Tomoharu Awaya, Yokohama, JP;
Assignee:
Fujitsu Limited, Kawasaki, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G06F / ;
U.S. Cl.
CPC ...
371 10 ; 365200 ;
Abstract
A semiconductor memory device having a redundancy configuration including a read circuit for a defective memory address. The read circuit includes a transistor which forms a current switch circuit with a bipolar-transistor of an input buffer circuit. The base electrode of the transistor is connected to the output terminal of a PROM which stores a defective address. The reading operation is carried out by applying a voltage lower than a normally applied voltage to the base electrode of the bipolar-transistor and detecting the base current.