The Design of a Fully Differential Capacitive Pressure Sensor with Unbalanced Parasitic Input Capacitances in 130nm CMOS Technology

摘要

A switched capacitor amplifier for measuring absolute pressure with a micro-machined capacitive pressure sensor using correlated double sampling has been designed in 130nm CMOS technology. The switched capacitor amplifier design uses a combination of correlated double sampling, input offset cancellation, and output offset cancellation to help reject 1/f noise and DC offset mismatch. A method for sizing the operational transconductance amplifier (OTA) components according to the system noise, accuracy, and bandwidth requirements is presented.