Ultralow-phase-noise oscillators based on BAW resonators

Abstract

This paper presents two 2.1-GHz low-phase noise oscillators based on BAW resonators. Both a single-ended common base structure and a differential Colpitts structure have been implemented in a 0.25-μm BiCMOS process. The detailed design methods including the realization, optimization, and test are reported. The differential Colpitts structure exhibits a phase noise 6.5 dB lower than the single-ended structure because of its good performance of power noise immunity. Comparison between the two structures is also carried out. The differential Colpitts structure shows a phase noise level of -87 dBc/Hz at 1-kHz offset frequency and a phase noise floor of -162 dBc/Hz, with an output power close to -6.5 dBm and a core consumption of 21.6 mW. Furthermore, with the proposed optimization methods, both proposed devices have achieved promising phase noise performance compared with state-of-the-art oscillators described in the literature. Finally, we briefly present the application of the proposed BAW oscillator to a micro-atomic clock.

Modeling Nonlinear Dynamics of Functionalization Layers: Enhancing Gas Sensor Sensitivity for Piezoelectrically Driven Microcantilever

“…The first resonance mode offers a prominent response spectrum, easing fit with the measured response, despite the findings that it produces insufficient energy trapping, with irregularities and erratic behavior in prominence . By tuning the values of G′ and G″ , the theoretical response curve can be shifted and the profile adjusted (refer to Figure ) for the resonances as defined from the BVD impedance response spectrum in both curves to coincide in shape and position. Series resonance is used because its value is related to the mechanical properties of the resonator, thereby providing information on the coating of the QCM. , …”

“…By employing the orthogonality principle between the modes, we obtained the ordinary differential equations where μ n denotes the linear model damping coefficients that can be measured experimentally and determined as shown in ref . M is the equivalent mass of the beam accounting for the adsorbed mass, and η i are time-independent coefficients whose definitions can be found in the Supporting Information.…”

A film bulk acoustic resonator oscillator based humidity sensor with graphene oxide as the sensitive layer

“…Since FBARs have many excellent properties such as high quality factor, high frequency and low power consumption, they have been extensively utilized to develop oscillators [10,11] with different circuit topologies for various applications. A low power FBAR pierce oscillator based on 0.18 μm CMOS with a frequency of 1.9 GHz was designed by Otis et al [11], and a Colpitts topology FBAR oscillator with temperature compensation by Pang et al [12].…”