An 8V 50μW 1.2MHz CMOS-MEMS oscillator

We report the design of a 50 μW 1.2 MHz monolithic MEMS oscillator embedded in a standard 0.35 μm CMOS with dc-bias lower than 8V. This is the first-time demonstration for a sub-100 μW single-chip CMOS-MEMS oscillator operated in MHz range. To overcome the motional impedance R
_m
> 8 MΩ under sub-10V dc-bias (VP), an ultra-low input referred noise (<; 25 fA/rtHz), high gain integrator-differentiator transimpedance amplifier (ID-TIA) is designed with only 50-150 μW power consumption. With V
_p
of 8V and 11V, the phase noise (PN) FOM of 146 dB and 177 dB is attained at 1-kHz offset, respectively, for sub-100μW operations. Moreover, the power FOM of 40.6 nW/kHz (V
_p
= 8V) and 52.8 nW/kHz (V
_p
= 11V) is also comparable with state-of-the-art low power CMOS and MEMS oscillators.