Quadrature VCO based on an LC-ring in 0.18-μm CMOS technology.

In this letter, a new LC-ring quadrature voltage-controlled oscillator (QVCO) is proposed. The proposed 0.18-μm CMOS QVCO uses a new composite LC resonator, and it occupies the die area of 0.61 × 0.95 mm2. At the supply voltage of 1.2 V, the total power consumption is 3.7 mW. The free-running frequency of the QVCO is tunable from 3.86 to 4.22 GHz as the tuning voltage is varied from 0.0 to 1.2 V. The measured phase noise at 1 MHz frequency offset is −123.42 dBc/Hz at the oscillation frequency of 3.94 GHz and the figure of merit of the proposed QVCO is −190.38 dBc/Hz. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 54:474-477, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26549 [ABSTRACT FROM AUTHOR]