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. 29, 1985
Filed:
Oct. 03, 1983
Steven D Millaway, Tucson, AZ (US);
Jerald G Graeme, Tucson, AZ (US);
Burr-Brown Corporation, Tucson, AZ (US);
Abstract
In a circuit in which a common-source junction field effect transistor (JFET) is cascoded with a JFET element, current diversion or division circuits are used to divert a majority of the current passing through the input amplifier stage so that it bypasses the cascode FET without compromising the primary circuit function. The bypassing function is achieved by a current mirror, a current mirror-like circuit, or similar devices such as current sources, current splitters and the like and the circuits may be ratioed to more precisely control the bypass current by the use of emitter area scaling, ratioed emitter degeneration resistors, or both. The resultant cascode circuit is relatively noise-free and can easily be implemented into a monolithic integrated circuit without using excess or unrealistic die areas. Another advantage is that the current dividers or diverters make it easier to bias the cascode FET and a further advantage is that the same techniques can be applied with other than JFET amplifier elements, and with other amplifier devices, differential stages, plural stages, and the like.