Design of Low Phase Noise with Wide-band VCO Using Source Capacitive Degeneration

This paper presents a completely integrated low phase noise and wide tuning range CMOS LC voltage controlled oscillator with a source capacitive degeneration and large accumulation-mode varactors(AMOS) for a wide-band receiver front-end by a TSMC 0.18-mum 1P6M CMOS process. AMOS varactors are used to maintain a large tuning range. However, the capacitors connect to source of cross-couple pairs to further reduce the parasitic capacitance and increase VCO tuning capability. The VCO consumes 11 mA from 1.2 V supply and operates with a wide-band from 3.69 - 5.75 GHz. The measured phase noise is less than -113.6 dBc /Hz at 1 MHz offset within the entire tuning range.