Ultra-Low Power CMOS Readout for Resonant MEMS Strain Sensors

This paper presents an ultra-low power, silicon-integrated readout for resonant MEMS strain sensors. The analogue readout implements a negative-resistance amplifier based on firstgeneration current conveyors (CCI) that, thanks to the reduced number of active elements, targets both low-power and low-noise. A prototype of the circuit was implemented in a 0.18-µm technology occupying less than 0.4 mm2 and consuming only 9 µA from the 1.8-V power supply. The prototype was earliest tested by connecting it to a resonant MEMS strain resonator.