METHODS OF BUILDING HIGH-PERFORMANCE ADC USING STRUCTURAL AND INFORMATION REDUNDANCY

Abstract

Most of the parasitic parameters of integrated circuits are capacitors, the application of the principles of amplification and conversion of currents has an advantage compared to the principle of conversion and amplification of voltages and digital-to-analog converters with current output are relevant. There are significant advantages of using redundant counting systems for the weights of digital-to-analog converters, which avoids gaps in the conversion characteristics of such digital-to-analog converters. The article describes the method of building multi-bit DACs with weight redundancy with current output. Such DACs make it possible to significantly (by an order of magnitude) increase the speed of bit-by-bit coding ADCs. It is shown that such a DAC has a high speed, and also ensures the continuity of the conversion characteristics, even under the conditions of using an imprecise element base. Methods of building multi-bit current digital-analog converters based on resistive matrices, especially on the basis of generators of the same bit currents, are considered. The methods of reducing the error of the superposition of the discharge weights in such digital-to-analog converters due to the use of discharge current generators with high output resistance have been investigated. The methods of using redundancy in multi-bit current digital-to-analog converters to increase the speed of the bit-by-bit balancing ADC, which they are part of, are analyzed. ADC circuits implementing accelerated balancing algorithms based on redundant positional counting systems are presented. The principle and functional schemes of push-pull DC amplifiers with current feedback for increasing the output resistance of digital-to-analog converters are presented. Estimates of the output resistance of the considered two-stroke DC amplifiers based on the results of analytical calculations and computer simulations are given.