A Single-Ended Charge-sharing Based Capacitance to Voltage Converter

A single-ended charge-sharing based capacitance to voltage converter (CVC) which is suitable for the sense of capacitance to ground is described. It uses on-chip capacitor array to provide stable compensation for the input fixed and parasitic capacitance. Three modes are performed successively to detect the absolute values of input fixed and parasitic capacitance, feedback capacitance, compensation error, and input variable capacitance precisely. Simulation results show that the maximum test error of the proposed CVC under different V&T environments is about 0.8 fF, which achieves a high-test resolution for capacitance sensing of a single-ended capacitor.