Patent Number: 6,396,360

Title: Method and circuitry for implementing an inductor-capacitor phase interpolated voltage-controlled oscillator

Abstract: Method and circuitry for implementing an inductor-capacitor voltage-controlled oscillator with improved overall performance. In an exemplary embodiment, the present invention includes two phase shifters and an interpolator. The two phase shifters are coupled to the interpolator in a loop configuration. That is, output from the two phase shifters are fed into the interpolator. The output of the interpolator, in turn, is fed back to the two phase shifters. The two phase shifters and the interpolator respectively utilize LC tanks having different fixed resonant frequencies, with the first phase shifter resonant frequency being the lowest, the interpolator resonant frequency being in the middle and the second phase shifter resonant frequency being the highest. Signals from the first and second phase shifters are selectively combined by the interpolator according to a control signal. Thus, the VCO can be continuously tuned near the resonant frequency of the interpolator.

Inventors: Cai; Yijun (Irvine, CA)

Assignee: Broadcom Corporation

International Classification: H03B 5/00 (20060101); H03B 5/08 (20060101); H03B 5/26 (20060101); H03B 5/12 (20060101); H03B 005/02 (); H03B 005/00 ()

Expiration Date: 05/28/2019