Methods to Improve Linearity of Signal’s Analog-to-Digital Conversion with Self-Calibration

This chapter is devoted to the development of embedded methods for ADCs and DACs, which will allow to reduce the impact of errors after manufacturing process through self-calibration systems by reducing the nonlinearity of the converter. Principles for the development of methods of linearity improvement for mixed-signal conversion by self-calibration have been proposed which, in contrast to known solutions, are more effective in reducing nonlinearity. The built-in feedback systems allow for a sufficient reduction of deflected parameters in the case of increasing the area on the die and calibration time within permissible limits. An embedded system for linearity improvement by self-calibration of flash analog-to-digital converter is proposed, in which, due to the inclusion of preamplifiers and calibration digital-to-analog converters in feedback as well as nonlinearity parameters have been reduced almost three times, due to increasing calibration time by only 12%. A built-in system for linearity improvement by self-calibration for digital-to-analog converter has been proposed, in which the nonlinearity parameters have been reduced by 20–25% due to the comparison and calibration of current sources, in the case of only 5% increase of occupied area. A method of linearity improvement for a pipeline analog-to-digital converter has been developed, in which the nonlinearity parameters have been reduced by approximately 2.5 times due to the introduction of an amplifier offset reduction system. Compared to the previous method, the gain error does not decrease.