Abstract

We present a design of FBAR (film bulk acoustic resonator) oscillator to achieve low phase noise. Between the series and parallel resonances, FBAR serves as an inductor in our design. We adopt the Colpitts topology for the oscillator due to its good phase noise performance. FBAR was modeled by Modified Butterworth-Van Dyke circuit in our design. Parasitic inductances of interconnects were well extracted and included in our simulation. By following the proper tuning guidelines, we demonstrated a FBAR oscillator at 1.6GHz with a phase noise of -95dBc/Hz at 10kHz offset and - 115dBc/Hz at 100kHz offset.

Keywords: FBAR, FBAR oscillator, phase noise, matching, parasitic estimation