Calibrated switched capacitor integrators based on current conveyors and its application to Delta Sigma ADC

In this paper a fully differential current conveyor based switched capacitor (SC) integrator is presented. To operate the current conveyor (CCII) integrator with high linearity, calibration is used to correct for its non idealities. Simulation results are presented to show the effectiveness of the calibration technique. The presented integrator is applied to design of a 2nd order Delta Sigma ADC. A comparison of the calibrated and uncalibrated ADC outputs reveals that the calibration technique improves the dynamic range and SNDR significantly. The oversampled ADC gives more than 85 dB DR and 76 dB SNDR for bandwidth of 0.5 MHz and clock frequency of 80 MHz respectively.

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