A novel low order delta–sigma modulator without harmonic distortion

The paper discusses a novel delta–sigma (ΔΣ) modulator structure, which compensates for the influence of a higher harmonic distortion to achieve a high resolution of up to 16 bits for the OSR = 100. The proposed approach combines the advantages of single-bit quantizer ΔΣ modulators with those provided by multi-bit ΔΣ devices. In the initial part of the article, we present the novel second-order structure, verify its correct functioning via the MATLAB simulation environment, and examine the requirements for a partial block. The related sections of the paper then analyze the design of a ΔΣ converter comprising the novel modulator structure and utilizing both the switched capacitor technique and the ONSemi I3T25 (350 nm) technology. The advantages and disadvantages of the discussed solution are evaluated, and the structure is compared with common versions of the ΔΣ modulator. The value of SNDR = 86 dB (ENOB = 14 bits) was achieved in the entire bandwidth.