Design of 900MHz voltage-controlled oscillator using 0.18μm CMOS technology

This paper presents the design of a 900 MHz LC oscillator implemented in 0.18 mum RF CMOS technology. Employing an on-chip PN varactor together with an on-chip spiral inductor, this voltage-controlled oscillator (VCO) achieves a simulated phase noise of - 100.9 dBc/Hz at a 100 kHz offset. The output frequency of the VCO can be tuned from 785 MHz to 955.6 MHz which correspond to 170.6 MHz tuning range, obtained by only tuning the control voltage to the diode varactor pairs. The VCO consumes 6.5 mW power from 1.6 V DC supply voltage.