A 995MHz fundamental nonlinear quartz MEMS oscillator

A quartz resonator operating at 995 MHz in the fundamental mode has been characterized in a closed loop oscillating system under different drive levels to determine its nonlinear behavior and optimum phase noise performance. The best phase noise achieved was -106 dBc/Hz at a 1 kHz offset frequency. The same quartz technology was used to build VCXOs in both the Colpitts and Pierce configurations at several frequencies above 650 MHz. The lowest phase noise level achieved in the Colpitts configuration operating at 705 MHz is -111 dBc/Hz at a 1 kHz offset frequency while a Pierce Oscillator operating at 662 MHz achieved a phase noise of -112.8 dBc/Hz at the same offset. Power consumption in these VCOs is typically on the order of 30-90 mW.