抄録
An application of the stochastic A/D conversion to multi-bit delta-sigma modulators is considered, and a novel correction technique for D/A converter (DAC) error is proposed. The stochastic A/D conversion can reduce the area of the quantizer and allows large mismatches. The proposed calibration technique corrects DAC errors using a programmable quantizer. The programmable quantizer has a non-linear characteristic that cancels DAC errors. Using this technique, we can decrease the influence of DAC errors without using conventional dynamic element matching. This A/D converter has a non-linear quantization characteristic, so output digital code must be corrected using a programmable encoder. This code correction and setting of the quantization levels are carried out based on calibration data obtained using genetic algorithm.
