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. 03, 2000
Filed:
Sep. 30, 1998
Dana Vincent Laub, Irvine, CA (US);
Julian L Tham, Irvine, CA (US);
Roy H Fladager, Irvine, CA (US);
Conexant Systems, Inc., Newport Beach, CA (US);
Abstract
The present invention includes a Voltage Controlled Oscillator (VCO) having a resonant circuit capable of being quickly switched between two resonant frequencies in order to generate two different LO frequencies. In a preferred embodiment, the present invention includes a VCO having a dual-frequency resonant circuit attached to the VCO's resonant circuit input leads. The dual-frequency resonant circuit is constructed in a differential architecture in order to create a number 'virtual ground' points within the circuit that nearly eliminate any ground currents, and thus minimize the time required to switch the resonant circuit between the two LO frequencies. The switching between two resonant frequencies is achieved by creating a short circuit across certain components within the circuit to eliminate them from the resonant circuit. The combination of the differential architecture dual-frequency resonant circuit with a single VCO provides for the power efficient and space-saving generation of both LO frequencies needed for a wireless transceiver. Moreover, by requiring only one resonant circuit, the area on the circuit board within the wireless transceiver is greatly reduced, resulting in a smaller transceiver circuit.