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:
Oct. 26, 1982
Filed:
Jun. 09, 1980
Hitachi, Ltd., Tokyo, JP;
Hitachi Ome Electric Co., Ltd., Tokyo, JP;
Abstract
A level conversion circuit for converting a signal of a polarity to a signal of the opposite polarity has differential pair transistors, push-pull type output transistors adapted to receive the differential outputs of opposite phases from the differential pair transistors, a plurality of protective transistors for protecting the output transistors and a capacitance separation element connected between the common collector outputs of the plurality of protective transistors and the output of one of the differential pair transistors. The protective transistor prevents both of the differential outputs from simultaneously taking high level due to various operating conditions of the conversion circuit. Therefore, the deterioration or breakdown of the output transistors caused by the through current is avoided. The capacitance separation element also contributes to prevent the reduction of operation speed of the differential transistors caused by the collector capacitances of the plurality of protective transistors.