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:
Dec. 12, 1989
Filed:
Oct. 19, 1988
SGS-Thomson Microelectronics s.r.l., Brianza, IT;
Abstract
The structure of a vertical PNP transistor with isolated collector is modified by forming a P-type diffusion outside the perimeter of a sinker collector diffusion to form an auxiliary collector capable of detecting the injection of current toward the substrate when the integrated transistor saturates. The current gathered by said auxiliary collector is used for activating a saturation limiting circuit formed by an NPN transistor which is switched-on when said said current gathered by said auxiliary collector reaches a threshold value and which in turn switches-on a PNP transistor having an emitter and a collector connected respectively to the emitter and to the base of the PNP vertical transistor with isolated collector for reducing the driving base current thereto.