Design of a high tuning range and low phase noise transformer-based LC voltage-controlled oscillator

Abstract

This article proposes a wide tuning voltage-controlled oscillator (VCO) by employing a transformer-based LC-tank and is fabricated in a TSMC 0.18 μm CMOS process with 1.5 V supply voltage. We choose decoupling effect to decrease primary and secondary inductances and then decrease quality factors to obtain higher oscillation frequency and wide tuning range. Measurement results show that at the supply voltage of 1.5 V, the proposed VCO is tunable from 5.96 GHz to 7.3 GHz corresponding to a tuning range of 20.1%, the measured phase noise is −110.9 dBc/Hz at 1 MHz offset from the oscillation frequency of 5.97 GHz, the total power consumption is 9.51 mW with an output signal power of −4.74 dBm at the frequency of 6.2 GHz. The chip area including pads occupies only 0.69 × 0.696 mm2. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:1165–1169, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25908