Dynamically switched low-phase-noise LC VCO with harmonic filtering

A novel load-independent switched LC VCO with PMOS dynamically switched current source and harmonic filtering is presented. The VCO has been designed and implemented with Jazz 0.18 μm CMOS process. At 5.47 GHz carrier frequency, the VCO achieves a measured phase noise of -122.4 and -102dBc/Hz at 1 MHz and 100 kHz offset, respectively. The VCO works between 5.3-5.7 GHz, which yields a tuning range of 400 MHz. This VCO consumes 4.2 mA from a 1.2 V supply and the figure-of-merit (FOM) is - 190.2 dBc/ Hz, which is among the best published FOM results for 5-6 GHz VCOs in standard CMOS process.