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:
Nov. 24, 1992
Filed:
Oct. 10, 1991
Raymond W MacKenzie, Baldwin Borough, PA (US);
Westinghouse Electric Corp., Pittsburgh, PA (US);
Abstract
A limiter circuit utilizes an RC circuit to provide negative feedback of the average value of the output signal of an amplifier, which may be an op-amp or a comparator, to the inverting input of the amplifier. The midpoint of the amplifier supply voltage is applied to the non-inverting input so that the amplifier operates in the linear range. This, combined with the elimination of the effects of offset produced by the negative feedback, results in a limiter circuit with increased sensitivity to small input signals and therefore extended dynamic range. Where a following circuit would be adversely affected by noise, hysteresis provided by positive feedback applied to the non-inverting input of the amplifier causes the limiter circuit to oscillate, at a frequency determined by the magnitude of the positive feedback and the time constant of the RC circuit providing the negative feedback, for input signals having an amplitude below a threshold set by the magnitude of the positive feedback.