A parasitic-insensitive charge transfer circuit for capacitive sensing based on switched capacitor integrator

Abstract

This paper introduces a parasitic-insensitive charge transfer circuit based on a switched capacitor integrator. The parasitic-insensitive charge transfer circuit includes four switches to eliminate parasitic capacitance. The degradation of sensitivity caused from parasitic capacitance was simulated with standard 0.35 μm CMOS technology and compared with that of a parasitic-sensitive charge transfer circuit. It can be concludes from the results, that even without the need of complicated circuits and additional touch schemes, the parasitic-insensitive can be effectively used in capacitive sensing for touch devices, such as a touch screen panel. © 2013 Springer Science+Business Media Dordrecht.