Integrated MEMS oscillator for cellular transceivers

RF MEMS reference oscillator platform with ±0.5ppm frequency stability for wireless handsets

“…A composite compensation factor FP that combines both the process spread of 8000 ppm [3] and the temperature drift of MEMS reference oscillator frequency (now 105 ppm across -40 to 85˚C) is generated using simple digital circuits. The frequency compensation logic shown in Fig.…”

“…MEMS fabrication tolerances lead to frequency offset error up to 8000 ppm [3], which can't be mitigated by SiO material temperature compensation, urging for electronic compensation [4,5]. The electronic compensation system essentially consists of temperature sensor, compensation circuitry and frequency tuning mechanism as shown in Fig.1.…”

CMOS-MEMS Oscillator Architecture and Phase Noise: A Mini-Review

“…Electronic oscillators are the most fundamental building block in almost any electronic system for a variety of applications such as frequency control (Achenbach et al, 2000) and environmental sensing (Bianchi et al, 2000;Walls and Gagnepain, 2002). In addition to traditional quartz resonator-based reference oscillators (Vittoz et al, 1988) and quartz crystal microbalance (QCM) sensors (Ferrari et al, 2006), miniaturized oscillators using microelectromechanical systems (MEMS) technology have been intensively studied in both academia and industry over the past two decades (Lavasani et al, 2011;Chance et al, 2014;Zaliasl et al, 2015;Naing et al, 2020;Kalia et al, 2021;Chang et al, 2022) to be used in demanding applications with size constraints. Among the existing MEMS oscillator fabrication approaches, the CMOS-MEMS technology is one of the most promising approaches to achieving the monolithic integration of mechanical resonators and electronic circuits (Xie et al, 2002;Dai et al, 2005;Chen et al, 2011;Li C.-S. et al, 2012;Chen et al, 2019;Valle et al, 2021).…”