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:
Aug. 25, 1992
Filed:
Dec. 19, 1990
Applicant:
Inventor:
Hiroshi Matsunaga, Kanagawa, JP;
Assignee:
Fujitsu Limited, Kanagawa, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03F / ;
U.S. Cl.
CPC ...
307446 ; 307443 ; 307455 ; 307475 ; 330253 ;
Abstract
A signal transmission circuit which transmits a signal over a transmission line includes a line driver circuit comprising a differential amplifier and an emitter follower circuit connected thereto, and a metal oxide semiconductor field-effect transistor which provides a high impedance when power supply from a power supply source is turned off and, thereby, causes the line driver circuit to provide a high output impedance to the transmission line when power supply is turned off.