A UHF SiGe push-pull quartz MEMS oscillator

Compact oscillators at UHF frequencies and below are challenging for IC designers because of the large size of the passive components, particularly the inductors. An integrated SiGe push-pull sustaining circuit fabricated in the IBM 7WL process eliminates the need for inductors. Combining this circuit with and an external quartz resonator allowed the development of 708 MHz and 744 MHz fundamental mode oscillators. The lowest phase noise achieved was −103dBc/Hz at a 1 kHz offset for the 708 MHz oscillator. Oscillator total power consumption is <20mW.