A Parasitic-Insensitive Charge Transfer Circuit for Capacitive Sensing Based on Switched Capacitor Integrator
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.
KeywordsTouch screen pane (TSP) Charge transfer circuit Parasitic capacitance Capacitive sensing Parasitic-sensitive circuit Parasitic-insensitive sensing
This work was supported in part by the Korea Institute of Energy Technology Evaluation and Planning (KETEP) and SNT company.
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