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:
Jul. 03, 2001
Filed:
Oct. 04, 1999
Hongmo Wang, Watchung, NJ (US);
Agere Systems Guardian Corp., Orlando, FL (US);
Abstract
A variable frequency oscillator (VFO) circuit having an increased frequency tuning range to selectively obtain operating frequencies above and below a set frequency. The circuit includes a tank inductor connected in parallel with a tank capacitor for primarily defining the set oscillating frequency of the VFO circuit. A switchable capacitor is included for selectively providing a predetermined step-wise decrease of the oscillating frequency to a frequency value below the set frequency of the circuit, and a varactor is included for accommodating selective tuning of the oscillating frequency within a range of frequency values below the set frequency. The inventive circuit selectively includes a switchable inductance element which is selectively electromagnetically coupled to the tank inductor to decrease the overall inductance value of the VFO circuit and, thereby, selectively increase the oscillating frequency above the set frequency value.