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:
Jan. 08, 1991
Filed:
Mar. 05, 1990
Minoru Tateno, Takasaki, JP;
Akira Ide, Takasaki, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A sense amplifier in a semiconductor memory device comprising a differential pair of bipolar transistors whose bases are supplied with read signals appearing on a pair of common data lines pulled up to the side of a positive power source potential, a regulated current circuit which causes a constant current to flow from the common emitters of the pair of bipolar transistors, as well as regulated current circuits which bias the respective bases of the pair of bipolar transistors to the side of a negative power source potential, and a control circuit which switches and controls the respective regulated current circuits in accordance with the select state of the sense amplifier, and also comprising saturation preventive circuits which cause minute currents to flow from the respective bases of the pair of bipolar transistors toward the negative power source potential, so that the bipolar transistors are avoided from falling into saturated states when the regulated current circuits are turned 'off,' thereby making it possible to reduce the average power consumption of the memory device without delaying the operating speed thereof.