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:
Feb. 05, 1991
Filed:
Dec. 26, 1989
Frederick G Weiss, Newberg, OR (US);
Other;
Abstract
A regenerative comparator with a differential amplifier pair of transistors (Q.sub.1D, Q.sub.1E, Q.sub.2D, and Q.sub.2E) and a differential regenerative pair of transistors (Q.sub.3D, Q.sub.3E, Q.sub.4D, and Q.sub.4E), utilizes one or more of the following three techniques to reduce hysteresis by reducing the amount of charge storage in transistors. First, the transistors are arranged in a bootstrap cascode configuration having a depletion mode device (Q.sub.D) and an enhancement mode device (Q.sub.E). Second, a differential amplifier pair source-coupling implementation (D.sub.1 -D.sub.4, Q.sub.5A -Q.sub.5C, and Q.sub.6A -Q.sub.6C) allows current to flow through the transistors of the differential amplifier pair and differential regenerative pair independent of whether current is flowing through the branch (52 or 4) that connects the emitters or sources of the enhancement devices of the amplifier pair and regenerative pair. Third, the comparator includes keep-alive current sources (Q.sub.KA1 -Q.sub.KA4) that allow current to flow through the amplifier pair and regenerative pair independent of the magnitude of the difference in gate input voltages being compared.