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:
Aug. 17, 1999
Filed:
Mar. 05, 1998
Scott Robert Humphreys, Boynton Beach, FL (US);
Darrell Eugene Davis, Sunrise, FL (US);
Barry W Herold, Delray Beach, FL (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A low input prescaler (800) that is responsive to input signals having low amplitude alternating current (AC) components includes a switched tunable prescaler (280) that generates a prescaler output signal (221) having a prescaler output frequency during an operational state of the prescaler and having a free-running frequency that is responsive to a tuning control signal (216) during a tuning state of the prescaler. A frequency comparator (235) generates a comparator output in response to a difference between a reference frequency and the prescaler output frequency. A prescaler tuner (290, 390) adjusts the tuning control signal in response to the comparator output during the tuning state to minimize the difference between the reference frequency and the prescaler output frequency, and holds the tuning control signal during the operational state. The prescaler is used in phase lock loops (200, 400, 600) and other circuits.