Sub-fF Resolution Capacitive Amplifier For Particulate Matter Airborne Detection

摘要

In this paper the preliminary design of the electronic interface for a particulate matter detector is reported. The topology relies on a simple capacitance to voltage converter capable of detecting capacitance variations in the attoFarad range. Theoretical analysis of the signal to noise ratio related to the geometry of the sensing channel is carried out. Simulation results supporting the validity of the theoretical analysis are reported and show a potential minimum detectable capacitance variation as low as 36 aF for each sensing electrode with a current dissipation of $20 mu mathrm{A}$.