Abstract
An analog-digital converter controller has an analog-digital converter and a digital calibration circuit. The analog-digital converter has a plural of levels converting circuit, the analog-digital converter is used for receiving an analog signal and generating a digital signal. The digital calibration circuit is used for receiving the digital signal, then generating a final digital signal according to a calibration-code table. There is at least one differential non-linearity (DNL) value corresponding to each level of the converting circuit, each DNL value is negative.