Overview of methods to increase linearity of high-performance ADC

摘要

This paper makes a review of main methods to improve the linearity of ADCs. Methods are collected in view of mainstream techniques. A model of redundant noise-shaping Pipelined Flash-SAR ADC is proposed, which is the combination of Flash, Pipeline, SAR and ΣΔ ADC, the effectiveness of the model is demonstrated by simulation. Also, application of dynamic element matching (DEM) linearization techniques to the ΣΔ ADC is verified in a third-order four-bit continuous-time ΣΔ modulator with a standard deviation of 1%. Finally, auxiliary DAC calibration technique to improve the linearity of ADC is verified by a concrete 12-bit SAR ADC chip.