1.5V 10-12.5 GHz Integrated CMOS Oscillators

This paper describes two integrated CMOS LC oscillators operating above 10 GHz. The first circuit is based on the ring-coupled quadrature voltage-controlled (VCO) configuration, while the other is a ring oscillator using inductive load. Fabricated in a 0.25 micron CMOS technology, both oscillators can operate from a single supply voltage as low as 1.5V. The highest operating frequencies for the quadrature VCO and ring oscillator are 11 and 12.55 GHz, respectively. The ring-coupled VCO exhibits a phase noise of -106 dBc/Hz at 1 MHz offset and achieves 1.24 GHz tuning range.