Abstract
In this letter, a 2.4 GHz FBAR-based Colpitts oscillator is designed using a film bulk acoustic resonator(FBAR) resonator with high-quality characteristics. The dynamictail-current biasing circuit allows the Colpitts transistors tooperate in the Class-AB regime, which helps to increase thecurrent efficiency and improve phase noise performance. The R Chigh-pass network is included to suppress the dc latch andlow-frequency instability of the FBAR-based oscillator. Theproposed oscillator core is fabricated in a 180 nm CMOStechnology, and it occupies an area of 0.6x0.53 mm2. Mea-surement results show that the oscillator achieves a phase noiseof-141.1 dBc/Hz@100 kHz offset with a figure-of-merit (FoM)of 226.4. The oscillator consumes a dc power of 1.82 mW undera supply voltage of 0.9 V.