Design of the low-noise LC oscillator with the digital frequency tuning based on the composite resonator

This paper presents a low phase noise differential LC oscillator with the new resonator type. The resonator architecture is an LC tank with an additional pair of serial resonators. The circuit was implemented in 0.18 μm CMOS technology and the measured phase noise reached -131.3 dBc at 3 MHz offset from a 6.776 GHz carrier with a power dissipation of 1.60 mW and the figure of merit (FOM) is -196.3 dB. The proposed area of application is the core of the local oscillator in a low-power wireless transceiver.